Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Income (Numerator)
Income available to common stockholders, Basic	$ 247,937	$ 374,607	$ 320,087
Income available to common stockholders after assumed conversions, Diluted	$ 247,937	$ 374,607	$ 320,087
Weighted Average Shares (Denominator)
Weighted shares, basic (in shares)	55,368,000	55,358,000	55,351,000
Weighted shares, diluted (in shares)	55,374,000	55,358,000	55,360,000
Earnings Per Share Basic and Diluted, Per Share Amounts [Abstract]
Basic (in dollars per share)	$ 4.48	$ 6.77	$ 5.78
Diluted (in dollars per share)	$ 4.48	$ 6.77	$ 5.78
Potentially dilutive securities (in shares)	0		0
Common stock
Earnings Per Share Basic and Diluted, Per Share Amounts [Abstract]
Potentially dilutive securities (in shares)		67,500
Options
Net Income (Numerator)
Effect of dilutive securities: Options	$ 0	$ 0	$ 0
Weighted Average Shares (Denominator)
Effect of dilutive securities: options (in shares)	6,000	0	9,000