Lessee, Operating Lease, Lease Not Yet Commenced. Undiscounted Cash Flows

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Payments to Acquire Strategic Investments

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Face (par) amount of debt instrument at time of issuance.

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- Definition

Term of lessee's operating lease not yet commenced, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Commitments and Contingencies - Narrative (Detail) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Aug. 31, 2020	Jun. 30, 2017
Operating Leased Assets [Line Items]
Operating lease costs		$ 100,000,000	$ 83,000,000
Operating lease liabilities, payments		75,000,000	59,000,000
Right-of-use assets obtained in exchange for operating lease liabilities		$ 223,000,000	112,000,000
Weighted-average remaining lease term		9 years
Weighted-average discount rate		3.00%
Undiscounted cash flows		$ 208,000,000
Payments for strategic investments		71,000,000	$ 12,000,000	$ 0
Unrecognized tax benefits		28,000,000
Letters of credit		21,000,000
2022 Notes
Operating Leased Assets [Line Items]
Principal		92,000,000				$ 782,500,000
2030 Notes
Operating Leased Assets [Line Items]
Principal		$ 1,500,000,000			$ 1,500,000,000
Celonis SE \| Forecast
Operating Leased Assets [Line Items]
Payments for strategic investments	$ 100,000,000
Minimum
Operating Leased Assets [Line Items]
Operating lease terms		4 years
Maximum
Operating Leased Assets [Line Items]
Operating lease terms		13 years