Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation Expense and Employee Benefit Plans - Stock Plan Narrative (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average exercise price, outstanding options (in dollars per share)	$ 21.23	$ 21.27	$ 20.76
2002 Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average exercise price, outstanding options (in dollars per share)	$ 30.29
2002 Stock Plan \| Class B common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation vesting period	4 years
Expiration period	10 years
Number of outstanding options (in shares)	48,777