Summary of Significant Accounting Policies Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Earnings Per Share [Abstract]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	815	24,004	19,928
Net income (loss)	$ 151,853	$ (184,093)	$ 232,117
Less income allocated to participating securities	(2,218)	(236)	(3,413)
Net income (loss) attributable to common stock	$ 149,635	$ (184,329)	$ 228,704
Basic (in dollars per share)	$ 8.69	$ (11.53)	$ 14.27
Basic (in shares)	17,212,000	15,992,000	16,027,000
Less income allocated to participating securities	$ (2,215)	$ (236)	$ (3,410)
Net income (loss) attributable to common stock	$ 149,638	$ (184,329)	$ 228,707
Diluted (in dollars per share)	$ 8.68	$ (11.53)	$ 14.26
Diluted (in shares)		15,992,000	16,041,000
Dilutive effect of stock options and restricted stock (in shares)	145,000	0	51,000
Adjusted weighted-average shares outstanding under treasury stock method (in shares)	17,357,000	15,992,000	16,078,000
Participating securities excluded under two-class method (in shares)	(126,000)	0	(37,000)
Adjusted weighted-average shares outstanding under two-class method (in shares)	17,231,000	15,992,000	16,041,000

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent, and if applicable, reduced by earnings allocated (not distributed) to participating securities under the two-class method to the extent that participating securities may share in earnings as if all of the earnings for the period had been distributed.

No definition available.