Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Basic Net Earnings Per Common Share [Abstract]
Earnings from continuing operations	$ 12,738	$ 22,654	$ 20,555	$ 13,104	$ 12,157	$ 19,273	$ 16,827	$ 8,597	$ 69,051	$ 56,854	$ 43,630
Loss from discontinued operations, net of taxes	$ (1,220)	$ (7,903)	$ (1,123)	$ (888)	$ (8,837)	$ (3,524)	$ (882)	$ (608)	(11,134)	(13,851)	(5,654)
Net earnings available to common stockholders									$ 57,917	$ 43,003	$ 37,976
Weighted average common shares outstanding (in shares)									22,378,414	22,456,480	22,726,491
Earnings from continuing operations per common share (in dollars per share)	$ 0.57	$ 1.01	$ 0.92	$ 0.58	$ 0.54	$ 0.86	$ 0.75	$ 0.38	$ 3.09	$ 2.53	$ 1.92
Loss from discontinued operations per common share (in dollars per share)									(0.50)	(0.62)	(0.25)
Net earnings per common share - Basic (in dollars per share)	$ 0.51	$ 0.66	$ 0.87	$ 0.54	$ 0.15	$ 0.70	$ 0.71	$ 0.36	$ 2.59	$ 1.91	$ 1.67
Diluted Net Earnings Per Common Share [Abstract]
Earnings from continuing operations	$ 12,738	$ 22,654	$ 20,555	$ 13,104	$ 12,157	$ 19,273	$ 16,827	$ 8,597	$ 69,051	$ 56,854	$ 43,630
Loss from discontinued operations, net of taxes	$ (1,220)	$ (7,903)	$ (1,123)	$ (888)	$ (8,837)	$ (3,524)	$ (882)	$ (608)	(11,134)	(13,851)	(5,654)
Net earnings available to common stockholders									$ 57,917	$ 43,003	$ 37,976
Weighted average common shares outstanding (in shares)									22,378,414	22,456,480	22,726,491
Plus incremental shares from assumed conversions [Abstract]
Dilutive effect of restricted stock and performance-based stock (in shares)									440,000	476,000	472,000
Weighted average common shares outstanding - Diluted (in shares)									22,818,451	22,931,723	23,198,392
Earnings from continuing operations per common share (in dollars per share)	$ 0.56	$ 1.00	$ 0.90	$ 0.57	$ 0.53	$ 0.84	$ 0.73	$ 0.37	$ 3.03	$ 2.48	$ 1.88
Loss from discontinued operations per common share (in dollars per share)									(0.49)	(0.60)	(0.24)
Net earnings per common share - Diluted (in dollars per share)	$ 0.50	$ 0.65	$ 0.85	$ 0.53	$ 0.14	$ 0.69	$ 0.69	$ 0.35	$ 2.54	$ 1.88	$ 1.64
Restricted and Performance Shares [Member]
Earnings Per Share, Diluted, Other Disclosures [Abstract]
Antidilutive securities excluded from computation of earnings per share (in shares)									255,000	249,000	248,000