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Share-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 07, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant under stock incentive plan (in shares)		1,300,000
Share-based compensation expense		$ 30,294	$ 26,669	$ 25,057
Tax benefit from share-based compensation		7,100	$ 6,400	$ 6,000
Nonvested awards, total compensation cost not yet recognized		$ 81,500
Nonvested awards, total compensation cost not yet recognized, period for recognition		6 years
Restricted stock granted in period (in shares)		1,218,613	1,134,581	928,324
Restricted stock granted in period, weighted average grant date fair value (usd per share)		$ 30.07	$ 25.98	$ 30.10
Restricted stock, vested in period, total fair value		$ 29,900	$ 23,200	$ 28,400
Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under stock incentive plan (in shares)		30,600,000
Class B \| Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under stock incentive plan (in shares)	36,100,000
Number of additional shares authorized under stock incentive plan (in shares)	5,500,000
Class B Common Stock Bonus
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period		3 years
Restricted stock granted in period (in shares)		726,613
Class B Common Stock Bonus \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period		3 years
Class B Common Stock Bonus \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period		10 years
Class B Common Stock Key Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period		10 years
Restricted stock granted in period (in shares)		492,000
Award vesting period		10 years
Subsidiary Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested awards, total compensation cost not yet recognized		$ 16,000
Nonvested awards, total compensation cost not yet recognized, period for recognition		2 years
Compensation and related expense		$ 9,400	$ 8,800	$ 7,900
Subsidiary Stock Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		3 years
Subsidiary Stock Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period		5 years