Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Earnings Per Share [Abstract]
Shares not included in computation of diluted weighted average earnings per common (in shares)	0	275
Net income attributable to common shareholders	$ 20,056	$ 6,261
Basic weighted average common shares outstanding (in shares)	5,779,000	6,104,000
Potentially dilutive common shares (in shares)	199,000	152,000
Diluted weighted average common shares outstanding (in shares)	5,978,000	6,256,000
Basic weighted average earnings per common share (in dollars per share)	$ 3.47	$ 1.03
Diluted weighted average earnings per common share (in dollars per share)	$ 3.35	$ 1.00