Earnings Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net earnings	$ 134,940	$ 208,115	$ 173,546
Weighted-average shares outstanding	57,053	54,187	54,325
Effect of dilutive stock awards	9,786	1,567	1,630
Weighted-average dilutive shares	66,839	55,754	55,955
Basic earnings per common share	$ 2.37	$ 3.84	$ 3.19
Diluted earnings per common share	$ 2.02	$ 3.73	$ 3.10
Restricted share units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted earnings per common share	32	1	0
Performance share units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted earnings per common share	107	3	290
Stock options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from diluted earnings per common share	295	949	1,109