Stockholders' Equity - Schedule of Changes in Stockholders' Equity (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Balance	$ 714,551	$ 660,417
Net income	10,612	15,318
Other comprehensive income (loss)	(11,123)	283
Equity compensation	3,826	4,151
Exercise of stock options	37	404
Issuance of shares pursuant to vesting of restricted stock units		1
Net payments for stock issuances and buybacks	(23,998)	(15,369)
Cumulative-effect adjustment for adoption of accounting principle	(513)
Dividends declared	(2,636)	(2,634)
Balance	690,756	662,571
Common Stock
Balance	$ 23	$ 22
Balance (in shares)	18,868	18,817
Exercise of stock options (in shares)	1	11
Issuance of shares pursuant to vesting of restricted stock units		$ 1
Issuance of shares pursuant to vesting of restricted stock units (in shares)	269	255
Net payments for stock issuances and buybacks (in shares)	(311)	(217)
Balance	$ 23	$ 23
Balance (in shares)	18,827	18,866
Additional Paid-in Capital
Balance	$ 346,795	$ 326,208
Equity compensation	3,826	4,151
Exercise of stock options	37	404
Balance	350,658	330,763
Retained Earnings
Balance	544,840	486,442
Net income	10,612	15,318
Cumulative-effect adjustment for adoption of accounting principle	(513)
Dividends declared	(2,636)	(2,634)
Balance	552,303	499,126
Treasury Stock
Balance	$ (164,963)	$ (139,704)
Balance (in shares)	3,978	3,629
Net payments for stock issuances and buybacks	$ (23,998)	$ (15,369)
Net payments for stock issuances and buybacks (in shares)	311	217
Balance	$ (188,961)	$ (155,073)
Balance (in shares)	4,289	3,846
Accumulated Other Comprehensive Loss
Balance	$ (12,144)	$ (12,551)
Other comprehensive income (loss)	(11,123)	283
Balance	$ (23,267)	$ (12,268)