Stock-Based Compensation - RSU Awards (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2021
Service Based RSU Awards
Number of Shares
Outstanding, beginning balance (in shares)	3,030,608		59,521		59,521
Granted (in shares)	3,438,602		2,674,863
Vested (in shares)	(1,328,876)		0
Forfeited (in shares)	(81,259)		(5,900)
Outstanding, beginning balance (in shares)	5,059,075	3,030,608	2,728,484	59,521	3,030,608
Weighted- Average Grant Date Fair Value (per share)
Outstanding, beginning balance (in dollars per share)	$ 34.94		$ 0.18		$ 0.18
Granted (in dollars per share)	10.19		36.56
Vested (in dollars per share)	33.38		0
Forfeited (in dollars per share)	35.83		36.63
Outstanding, beginning balance (in dollars per share)	$ 18.38	$ 34.94	$ 35.76	$ 0.18	$ 34.94
Weighted- Average Contractual Life (years)
Outstanding	1 year 1 month 6 days	1 year 3 months 18 days	1 year 10 months 24 days	2 years 4 months 24 days
Aggregate Intrinsic Value
Outstanding	$ 50,043	$ 46,700	$ 103,500	$ 2,000
Performance Shares
Number of Shares
Outstanding, beginning balance (in shares)	492,727		0		0
Granted (in shares)	0		438,403
Vested (in shares)	0		0
Forfeited (in shares)	(52,941)		0
Outstanding, beginning balance (in shares)	439,786	492,727	438,403	0	492,727
Weighted- Average Grant Date Fair Value (per share)
Outstanding, beginning balance (in dollars per share)	$ 30.07		$ 0		$ 0
Granted (in dollars per share)	0		30.84
Vested (in dollars per share)	0		0
Forfeited (in dollars per share)	30.84		0
Outstanding, beginning balance (in dollars per share)	$ 29.97	$ 30.07	$ 30.84	$ 0	$ 30.07
Weighted- Average Contractual Life (years)
Outstanding	1 year 9 months 18 days	2 years 2 months 12 days	2 months 12 days	0 years
Aggregate Intrinsic Value
Outstanding	$ 4,385	$ 7,600	$ 16,600	$ 0

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

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