Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) $ in Thousands		Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balances (in shares) at Dec. 31, 2020		111,830,857
Balances at Dec. 31, 2020		$ 1,118	$ 876,433	$ 246,242	$ 150	$ 1,123,943
Net income		0	0	102,161	0	102,161
Comprehensive income (loss), net of tax		$ 0	0	0	(321)	(321)
Release of restricted stock units, net of tax (in shares)		29,808
Release of restricted stock units, net of tax		$ 0	(609)	0	0	(609)
Release of performance stock units, net of tax (in shares)		61,654
Release of performance stock units, net of tax		$ 1	(1,901)	0	0	(1,900)
Share-based compensation costs		$ 0	5,701	0	0	5,701
Stock options exercised (in shares)		158,568
Stock options exercised		$ 2	1,743	0	0	1,745
Balances (in shares) at Mar. 31, 2021		112,080,887
Balances at Mar. 31, 2021		$ 1,121	881,367	348,403	(171)	1,230,720
Balances (in shares) at Dec. 31, 2020		111,830,857
Balances at Dec. 31, 2020		$ 1,118	876,433	246,242	150	1,123,943
Net income						$ 215,890
Shares repurchased and retired (in shares)	[1],[2]					0
Shares repurchased and retired	[2]					$ 0
Balances (in shares) at Jun. 30, 2021		112,223,991
Balances at Jun. 30, 2021		$ 1,122	895,227	462,132	(214)	1,358,267
Balances (in shares) at Mar. 31, 2021		112,080,887
Balances at Mar. 31, 2021		$ 1,121	881,367	348,403	(171)	1,230,720
Net income		0	0	113,729	0	113,729
Comprehensive income (loss), net of tax		$ 0	0	0	(43)	(43)
Release of restricted stock units, net of tax (in shares)		43,036
Release of performance stock units, net of tax		$ 1	0	0	0	$ 1
Shares repurchased and retired (in shares)	[1],[2]					0
Shares repurchased and retired	[2]					$ 0
Share-based compensation costs		$ 0	12,823	0	0	12,823
Stock options exercised (in shares)		100,068
Stock options exercised		$ 0	1,037	0	0	1,037
Balances (in shares) at Jun. 30, 2021		112,223,991
Balances at Jun. 30, 2021		$ 1,122	895,227	462,132	(214)	$ 1,358,267
Balances (in shares) at Dec. 31, 2021		111,303,140				111,303,140
Balances at Dec. 31, 2021		$ 1,113	827,725	710,088	(180)	$ 1,538,746
Net income		0	0	162,928	0	162,928
Comprehensive income (loss), net of tax		$ 0	0	0	(184)	(184)
Release of restricted stock units, net of tax (in shares)		115,686
Release of restricted stock units, net of tax		$ 1	(2,720)	0	0	(2,719)
Release of performance stock units, net of tax (in shares)		294,344
Release of performance stock units, net of tax		$ 3	(8,113)	0	0	(8,110)
Shares repurchased and retired (in shares)		(2,096,660)
Shares repurchased and retired		$ (21)	(131,768)	0	0	(131,789)
Dividends declared		0	0	(16,480)	0	(16,480)
Share-based compensation costs		$ 0	8,734	0	0	8,734
Balances (in shares) at Mar. 31, 2022		109,616,510
Balances at Mar. 31, 2022		$ 1,096	693,858	856,536	(364)	$ 1,551,126
Balances (in shares) at Dec. 31, 2021		111,303,140				111,303,140
Balances at Dec. 31, 2021		$ 1,113	827,725	710,088	(180)	$ 1,538,746
Net income						$ 309,691
Shares repurchased and retired (in shares)	[1],[2]					(5,115,000)
Shares repurchased and retired	[2]					$ (299,773)
Balances (in shares) at Jun. 30, 2022		106,841,360				106,841,360
Balances at Jun. 30, 2022		$ 1,068	541,797	987,273	(983)	$ 1,529,155
Balances (in shares) at Mar. 31, 2022		109,616,510
Balances at Mar. 31, 2022		$ 1,096	693,858	856,536	(364)	1,551,126
Net income		0	0	146,763	0	146,763
Comprehensive income (loss), net of tax		$ 0	0	0	(619)	(619)
Release of restricted stock units, net of tax (in shares)		140,899
Release of restricted stock units, net of tax		$ 1	(2)	0	0	(1)
Release of performance stock units, net of tax (in shares)		307
Release of performance stock units, net of tax		$ 0	(8)	0	0	$ (8)
Shares repurchased and retired (in shares)		(3,018,031)				(3,018,000)	[1],[2]
Shares repurchased and retired		$ (30)	(167,954)	0	0	$ (167,984)	[2]
Dividends declared		0	0	(16,026)	0	(16,026)
Share-based compensation costs		$ 0	14,099	0	0	14,099
Stock options exercised (in shares)		101,675
Stock options exercised		$ 1	1,804	0	0	$ 1,805
Balances (in shares) at Jun. 30, 2022		106,841,360				106,841,360
Balances at Jun. 30, 2022		$ 1,068	$ 541,797	$ 987,273	$ (983)	$ 1,529,155

[1] All shares repurchased have been retired and constitute authorized but unissued shares.

[2] Shares repurchased reflect repurchases settled during the three and six months ended June 30, 2022. These amounts exclude repurchases, if any, traded but not yet settled on or before June 30, 2022.