Investments - Additional Information (Detail) - USD ($) shares in Millions, $ in Millions |
6 Months Ended | |
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Jun. 30, 2019 |
Dec. 31, 2018 |
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| Investments [Line Items] | ||
| Held-to-maturity investments | $ 213 | $ 188 |
| Foreign government debt, after five years through ten years | 44 | |
| Investments in CLOs, after ten years | $ 169 | |
| PennyMac [Member] | ||
| Investments [Line Items] | ||
| Ownership percentage | 20.00% | |
| Shares | 16 | |
| Carrying value - equity method investment | $ 414 | 397 |
| Market value of equity method investments | $ 345 | $ 331 |
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- Definition Equity method investments shares owned. No definition available.
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- Definition Investments [Line Items] No definition available.
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value portion of investments accounted under the equity method. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing after tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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