Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, after accumulated amortization, of debt premium.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk. Excludes cumulative basis adjustment related to foreign exchange risk.

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Amount of long-term debt and lease obligation, including portion classified as current.

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No definition available.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Borrowings - Long-term Debt Including Unamortized Debt Discounts and Premiums (Details) - USD ($) $ in Millions							3 Months Ended
	Nov. 14, 2035	Aug. 24, 2033	May 19, 2033	Nov. 14, 2030	Nov. 17, 2028	May 19, 2028	Mar. 31, 2026	Dec. 31, 2025
Debt Instrument [Line Items]
Finance lease liabilities							$ 30	$ 37
Unamortized premium — net							29	33
Debt issuance costs							(76)	(82)
Fair value hedging basis adjustments							(97)	11
Total long-term debt							20,486	22,199
CSC Senior Notes
Debt Instrument [Line Items]
Senior notes							20,519	22,119
CSC Fixed-Rate Senior Notes \| 3.450% due February 13, 2026
Debt Instrument [Line Items]
Senior notes							$ 0	350
Fixed interest rate (percent)							3.45%
CSC Fixed-Rate Senior Notes \| 0.900% due March 11, 2026
Debt Instrument [Line Items]
Senior notes							$ 0	1,250
Fixed interest rate (percent)							0.90%
CSC Fixed-Rate Senior Notes \| 1.150% due May 13, 2026
Debt Instrument [Line Items]
Senior notes							$ 1,000	1,000
Fixed interest rate (percent)							1.15%
CSC Fixed-Rate Senior Notes \| 5.875% due August 24, 2026
Debt Instrument [Line Items]
Senior notes							$ 1,000	1,000
Fixed interest rate (percent)							5.875%
CSC Fixed-Rate Senior Notes \| 3.200% due March 2, 2027
Debt Instrument [Line Items]
Senior notes							$ 650	650
Fixed interest rate (percent)							3.20%
CSC Fixed-Rate Senior Notes \| 2.450% due March 3, 2027
Debt Instrument [Line Items]
Senior notes							$ 1,500	1,500
Fixed interest rate (percent)							2.45%
CSC Fixed-Rate Senior Notes \| 3.300% due April 1, 2027
Debt Instrument [Line Items]
Senior notes							$ 744	744
Fixed interest rate (percent)							3.30%
CSC Fixed-Rate Senior Notes \| 3.200% due January 25, 2028
Debt Instrument [Line Items]
Senior notes							$ 700	700
Fixed interest rate (percent)							3.20%
CSC Fixed-Rate Senior Notes \| 2.000% due March 20, 2028
Debt Instrument [Line Items]
Senior notes							$ 1,250	1,250
Fixed interest rate (percent)							2.00%
CSC Fixed-Rate Senior Notes \| 4.000% due February 1, 2029
Debt Instrument [Line Items]
Senior notes							$ 600	600
Fixed interest rate (percent)							4.00%
CSC Fixed-Rate Senior Notes \| 3.250% due May 22, 2029
Debt Instrument [Line Items]
Senior notes							$ 600	600
Fixed interest rate (percent)							3.25%
CSC Fixed-Rate Senior Notes \| 2.750% due October 1, 2029
Debt Instrument [Line Items]
Senior notes							$ 475	475
Fixed interest rate (percent)							2.75%
CSC Fixed-Rate Senior Notes \| 4.625% due March 22, 2030
Debt Instrument [Line Items]
Senior notes							$ 500	500
Fixed interest rate (percent)							4.625%
CSC Fixed-Rate Senior Notes \| 1.650% due March 11, 2031
Debt Instrument [Line Items]
Senior notes							$ 750	750
Fixed interest rate (percent)							1.65%
CSC Fixed-Rate Senior Notes \| 2.300% due May 13, 2031
Debt Instrument [Line Items]
Senior notes							$ 750	750
Fixed interest rate (percent)							2.30%
CSC Fixed-Rate Senior Notes \| 1.950% due December 1, 2031
Debt Instrument [Line Items]
Senior notes							$ 850	850
Fixed interest rate (percent)							1.95%
CSC Fixed-Rate Senior Notes \| 2.900% due March 3, 2032
Debt Instrument [Line Items]
Senior notes							$ 1,000	1,000
Fixed interest rate (percent)							2.90%
CSC Floating-Rate Senior Notes \| SOFR + 0.520% due May 13, 2026
Debt Instrument [Line Items]
Senior notes							$ 500	500
Basis spread (percent)							0.52%
CSC Floating-Rate Senior Notes \| SOFR + 1.050% due March 3, 2027
Debt Instrument [Line Items]
Senior notes							$ 500	500
Basis spread (percent)							1.05%
CSC Fixed-To-Floating Rate Senior Notes \| 5.643% due May 19, 2029
Debt Instrument [Line Items]
Senior notes							$ 1,200	1,200
Fixed interest rate (percent)							5.643%
CSC Fixed-To-Floating Rate Senior Notes \| 5.643% due May 19, 2029 \| Forecast
Debt Instrument [Line Items]
Basis spread (percent)						2.21%
CSC Fixed-To-Floating Rate Senior Notes \| 6.196% due November 17, 2029
Debt Instrument [Line Items]
Senior notes							$ 1,300	1,300
Fixed interest rate (percent)							6.196%
CSC Fixed-To-Floating Rate Senior Notes \| 6.196% due November 17, 2029 \| Forecast
Debt Instrument [Line Items]
Basis spread (percent)					1.878%
CSC Fixed-To-Floating Rate Senior Notes \| 4.343% due November 14, 2031
Debt Instrument [Line Items]
Senior notes							$ 1,000	1,000
Fixed interest rate (percent)							4.343%
CSC Fixed-To-Floating Rate Senior Notes \| 4.343% due November 14, 2031 \| Forecast
Debt Instrument [Line Items]
Basis spread (percent)				0.94%
CSC Fixed-To-Floating Rate Senior Notes \| 5.853% due May 19, 2034
Debt Instrument [Line Items]
Senior notes							$ 1,300	1,300
Fixed interest rate (percent)							5.853%
CSC Fixed-To-Floating Rate Senior Notes \| 5.853% due May 19, 2034 \| Forecast
Debt Instrument [Line Items]
Basis spread (percent)			2.50%
CSC Fixed-To-Floating Rate Senior Notes \| 6.136% due August 24, 2034
Debt Instrument [Line Items]
Senior notes							$ 1,350	1,350
Fixed interest rate (percent)							6.136%
CSC Fixed-To-Floating Rate Senior Notes \| 6.136% due August 24, 2034 \| Forecast
Debt Instrument [Line Items]
Basis spread (percent)		2.01%
CSC Fixed-To-Floating Rate Senior Notes \| 4.914% due November 14, 2036
Debt Instrument [Line Items]
Senior notes							$ 1,000	1,000
Fixed interest rate (percent)							4.914%
CSC Fixed-To-Floating Rate Senior Notes \| 4.914% due November 14, 2036 \| Forecast
Debt Instrument [Line Items]
Basis spread (percent)	1.23%
Ameritrade Holding Senior Notes
Debt Instrument [Line Items]
Senior notes							$ 81	81
Ameritrade Holding Fixed-Rate Senior Notes \| 3.300% due April 1, 2027
Debt Instrument [Line Items]
Senior notes							$ 56	56
Fixed interest rate (percent)							3.30%
Ameritrade Holding Fixed-Rate Senior Notes \| 2.750% due October 1, 2029
Debt Instrument [Line Items]
Senior notes							$ 25	$ 25
Fixed interest rate (percent)							2.75%