Basis of presentation (Tables)

9 Months Ended

Sep. 30, 2019

Accounting Policies [Abstract]

Summary of Basic and Diluted Earnings Per Common Share

The following is a summary of the basic and diluted earnings per common share calculation for each of the periods presented:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2019			2018			2019			2018
Basic earnings per common share calculation:
Net income	$	23,966		$	21,377		$	62,242		$	63,196
Dividends paid on and undistributed earnings allocated to participating securities	(128		)	(114		)	(333		)	(337		)
Earnings attributable to common shareholders	$	23,838		$	21,263		$	61,909		$	62,859
Weighted-average basic shares outstanding	30,899,583			30,692,668			30,849,035			30,661,852
Basic earnings per common share	$	0.77		$	0.69		$	2.01		$	2.05
Diluted earnings per common share:
Earnings attributable to common shareholders	23,838			21,263			61,909			62,859
Weighted-average basic shares outstanding	30,899,583			30,692,668			30,849,035			30,661,852
Weighted-average diluted shares contingently issuable	525,990			646,960			529,751			636,802
Weighted-average diluted shares outstanding	31,425,573			31,339,628			31,378,786			31,298,654
Diluted earnings per common share	$	0.76		$	0.68		$	1.97		$	2.01