Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Adoption of accounting pronouncement	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Retained Earnings Adoption of accounting pronouncement
Balance at beginning of period at Dec. 31, 2019	$ 1,143,683	$ (558)	$ 115	$ 1,127,487	$ (19,986)	$ 36,067	$ (558)
Balance at beginning of period (in shares) at Dec. 31, 2019			115,120
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	89,915					89,915
Other comprehensive income (loss)	(13,700)				(13,700)
Dividends declared	(39,441)					(39,441)
Net issuances of restricted stock	0		$ 1	(1)
Net issuances of restricted stock (in shares)			745
Stock-based compensation	13,525			13,525
Repurchases of common stock	(63,499)		$ (1)			(63,498)
Repurchases of common stock (in shares)			(1,263)
Balance at end of period at Mar. 31, 2020	$ 1,129,925		$ 115	1,141,011	(33,686)	22,485
Balance at end of period (in shares) at Mar. 31, 2020			114,602
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends, per share (in usd per share)	$ 0.34
Balance at beginning of period at Dec. 31, 2019	$ 1,143,683	$ (558)	$ 115	1,127,487	(19,986)	36,067	$ (558)
Balance at beginning of period (in shares) at Dec. 31, 2019			115,120
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	136,111
Other comprehensive income (loss)	(7,166)
Balance at end of period at Jun. 30, 2020	1,156,706		$ 115	1,154,046	(27,152)	29,697
Balance at end of period (in shares) at Jun. 30, 2020			114,635
Balance at beginning of period at Mar. 31, 2020	1,129,925		$ 115	1,141,011	(33,686)	22,485
Balance at beginning of period (in shares) at Mar. 31, 2020			114,602
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	46,196					46,196
Other comprehensive income (loss)	6,534				6,534
Dividends declared	(38,975)					(38,975)
Net issuances of restricted stock (in shares)			33
Stock-based compensation	13,035			13,035
Repurchases of common stock	(9)		$ 0			(9)
Repurchases of common stock (in shares)			0
Balance at end of period at Jun. 30, 2020	$ 1,156,706		$ 115	1,154,046	(27,152)	29,697
Balance at end of period (in shares) at Jun. 30, 2020			114,635
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends, per share (in usd per share)	$ 0.34
Balance at beginning of period at Dec. 31, 2020	$ 1,205,289		$ 113	1,179,972	(4,732)	29,936
Balance at beginning of period (in shares) at Dec. 31, 2020			113,128
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	110,598					110,598
Other comprehensive income (loss)	(8,797)				(8,797)
Dividends declared	(43,300)					(43,300)
Net issuances of restricted stock	0		$ 1	(1)
Net issuances of restricted stock (in shares)			602
Stock-based compensation	14,182			14,182
Repurchases of common stock	(80,273)		$ (1)			(80,272)
Repurchases of common stock (in shares)			(1,048)
Balance at end of period at Mar. 31, 2021	$ 1,197,699		$ 113	1,194,153	(13,529)	16,962
Balance at end of period (in shares) at Mar. 31, 2021			112,682
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends, per share (in usd per share)	$ 0.38
Balance at beginning of period at Dec. 31, 2020	$ 1,205,289		$ 113	1,179,972	(4,732)	29,936
Balance at beginning of period (in shares) at Dec. 31, 2020			113,128
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	259,811
Other comprehensive income (loss)	(4,360)
Balance at end of period at Jun. 30, 2021	1,259,250		$ 112	1,208,056	(9,092)	60,174
Balance at end of period (in shares) at Jun. 30, 2021			111,970
Balance at beginning of period at Mar. 31, 2021	1,197,699		$ 113	1,194,153	(13,529)	16,962
Balance at beginning of period (in shares) at Mar. 31, 2021			112,682
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	149,213					149,213
Other comprehensive income (loss)	4,437				4,437
Dividends declared	(42,720)					(42,720)
Net issuances of restricted stock (in shares)			5
Stock-based compensation	13,903			13,903
Repurchases of common stock	(63,282)		$ (1)			(63,281)
Repurchases of common stock (in shares)			(717)
Balance at end of period at Jun. 30, 2021	$ 1,259,250		$ 112	$ 1,208,056	$ (9,092)	$ 60,174
Balance at end of period (in shares) at Jun. 30, 2021			111,970
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cash dividends, per share (in usd per share)	$ 0.38