Stockholders' Equity - Additional Information (Details)		12 Months Ended
	Jun. 20, 2013 shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) director $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2006 shares	Dec. 06, 2021 USD ($)	Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of directors' stock grant vested on one year anniversary date		100.00%	100.00%
Granted (in dollars per share) | $ / shares		$ 186.08	$ 123.89	$ 110.56
Total unrecognized compensation cost related to nonvested shares of common stock granted | $		$ 37,300,000
Weighted average period of cost recognized		2 years 10 months 24 days
Fair value of shares vested | $		$ 14,100,000	$ 12,200,000	$ 9,400,000
Compensation expense related to nonvested stock grants | $		$ 15,900,000	$ 14,300,000	$ 9,600,000
Price of shares issued under employee stock purchase plan as a percentage of FMV					95.00%
Number of shares reserved for the employee stock purchase plan (in shares)					250,000
Additional shares authorized for issuance (in shares)	250,000
Shares redeemed to satisfy personal tax obligations (in shares)		63,028	78,767	107,461
Treasury stock, shares, forfeited for terminated employees		1,556
Stock repurchase program, authorized amount | $						$ 250,000,000
Repurchase of common stock (in shares)		634,869
Treasury stock, value, acquired, cost method | $		$ 83,700,000
Stock repurchase program, remaining authorized repurchase amount | $		$ 166,300,000
Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vested shares		5 years
Independent Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested stock grants to Independent directors (in shares)		7,200	9,900	17,880
2018 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved and available for issuance (in shares)							2,210,544
Common stock available for issuance (in shares)							1,746,779
Period of vested shares		5 years
2018 Long-Term Incentive Plan | Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested stock grants to employees (in shares)		109,985	114,680	163,250
2018 Long-Term Incentive Plan | Consultant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested stock grants to employees (in shares)		5,735	10,890
Second Amended and Restated 2005 Non-Employee Directors Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vested shares		1 year
Second Amended and Restated 2005 Non-Employee Directors Compensation Plan | Lead Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested stock grants to Independent directors (in shares)		3,500
Percentage of directors' stock grant vested on one year anniversary date		33.33%
Percentage of directors stock grant vested on grant date		33.33%
Percentage of directors stock grant vested on two year anniversary date		33.33%
Nonvested stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value, outstanding | $		$ 7,400,000
Nonvested stock | Independent Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Nonvested stock grants to Independent directors (in shares)			775
Number of retiring directors | director			1