Earnings Per Share (Tables)

6 Months Ended

Jun. 30, 2018

Earnings Per Share [Abstract]

Computation of Earnings Per Common Share

	Three Months Ended				Six Months Ended
	June 30,				June 30,
(in thousands, except per share data)	2018		2017		2018		2017
Numerator:
Net income to common shareholders	$	71,177	$	52,267	$	143,652	$	101,281
Net income allocated to participating securities - basic and diluted		1,328		1,166		2,694		2,322
Net income allocated to common shareholders - basic and diluted	$	69,849	$	51,101	$	140,958	$	98,959
Denominator:
Weighted-average common shares - basic	$	85,305	$	84,614	$	85,273	$	84,489
Dilutive potential common shares		178		253		178		266
Weighted-average common shares - diluted	$	85,483	$	84,867	$	85,451	$	84,755
Earnings per common share:
Basic	$	0.82	$	0.60	$	1.65	$	1.17
Diluted	$	0.82	$	0.60	$	1.65	$	1.17