Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Earnings Per Share [Abstract]
Shares not included in computation of diluted weighted average earnings per common (in shares)	0	0	0	200,000
Net income attributable to common shareholders	$ 23,232	$ 8,834	$ 59,432	$ 22,624
Basic weighted average common shares outstanding (in shares)	5,847,000	5,900,000	5,831,000	5,960,000
Potentially dilutive common shares (in shares)	247,000	104,000	214,000	123,000
Diluted weighted average common shares outstanding (in shares)	6,094,000	6,004,000	6,045,000	6,083,000
Basic weighted average earnings per common share (in dollars per share)	$ 3.97	$ 1.50	$ 10.19	$ 3.80
Diluted weighted average earnings per common share (in dollars per share)	$ 3.81	$ 1.47	$ 9.83	$ 3.72