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 (in shares) at Dec. 31, 2019			115,120
Balance at beginning of period at Dec. 31, 2019	$ 1,143,683	$ (558)	$ 115	$ 1,127,487	$ (19,986)	$ 36,067	$ (558)
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 (in shares)			745
Net issuances of restricted stock	0		$ 1	(1)
Stock-based compensation	13,525			13,525
Repurchases of common stock (in shares)			(1,263)
Repurchases of common stock	(63,499)		$ (1)			(63,498)
Balance at end of period (in shares) at Mar. 31, 2020			114,602
Balance at end 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 Dec. 31, 2019			115,120
Balance at beginning of period at Dec. 31, 2019	1,143,683	$ (558)	$ 115	1,127,487	(19,986)	36,067	$ (558)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	211,860
Other comprehensive income (loss)	3,990
Balance at end of period (in shares) at Sep. 30, 2020			114,180
Balance at end of period at Sep. 30, 2020	1,194,029		$ 114	1,167,109	(15,996)	42,802
Balance at beginning of period (in shares) at Mar. 31, 2020			114,602
Balance at beginning of period at Mar. 31, 2020	1,129,925		$ 115	1,141,011	(33,686)	22,485
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 (in shares)			0
Repurchases of common stock	(9)		$ 0			(9)
Balance at end of period (in shares) at Jun. 30, 2020			114,635
Balance at end of period at Jun. 30, 2020	1,156,706		$ 115	1,154,046	(27,152)	29,697
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	75,749					75,749
Other comprehensive income (loss)	11,156				11,156
Dividends declared	(38,969)					(38,969)
Net issuances of restricted stock (in shares)			(2)
Stock-based compensation	13,063			13,063
Repurchases of common stock (in shares)			(453)
Repurchases of common stock	(23,676)		$ (1)			(23,675)
Balance at end of period (in shares) at Sep. 30, 2020			114,180
Balance at end of period at Sep. 30, 2020	1,194,029		$ 114	1,167,109	(15,996)	42,802
Balance at beginning of period (in shares) at Dec. 31, 2020			113,128
Balance at beginning of period at Dec. 31, 2020	1,205,289		$ 113	1,179,972	(4,732)	29,936
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 (in shares)			602
Net issuances of restricted stock	0		$ 1	(1)
Stock-based compensation	14,182			14,182
Repurchases of common stock (in shares)			(1,048)
Repurchases of common stock	(80,273)		$ (1)			(80,272)
Balance at end of period (in shares) at Mar. 31, 2021			112,682
Balance at end 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 Dec. 31, 2020			113,128
Balance at beginning of period at Dec. 31, 2020	1,205,289		$ 113	1,179,972	(4,732)	29,936
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	430,682
Other comprehensive income (loss)	(14,368)
Balance at end of period (in shares) at Sep. 30, 2021			111,229
Balance at end of period at Sep. 30, 2021	1,316,043		$ 111	1,222,117	(19,100)	112,915
Balance at beginning of period (in shares) at Mar. 31, 2021			112,682
Balance at beginning of period at Mar. 31, 2021	1,197,699		$ 113	1,194,153	(13,529)	16,962
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 (in shares)			(717)
Repurchases of common stock	(63,282)		$ (1)			(63,281)
Balance at end of period (in shares) at Jun. 30, 2021			111,970
Balance at end of period at Jun. 30, 2021	1,259,250		$ 112	1,208,056	(9,092)	60,174
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	170,871					170,871
Other comprehensive income (loss)	(10,008)				(10,008)
Dividends declared	(42,463)					(42,463)
Net issuances of restricted stock (in shares)			1
Stock-based compensation	14,061			14,061
Repurchases of common stock (in shares)			(742)
Repurchases of common stock	(75,668)		$ (1)			(75,667)
Balance at end of period (in shares) at Sep. 30, 2021			111,229
Balance at end of period at Sep. 30, 2021	$ 1,316,043		$ 111	$ 1,222,117	$ (19,100)	$ 112,915