Earnings Per Share (Tables)

6 Months Ended

Jun. 30, 2016

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)	2016		2015		2016		2015
Numerator:
Net income to common shareholders	$	46,907	$	34,829	$	50,746	$	74,988
Net income allocated to participating securities - basic and diluted		1,136		766		1,233		1,701
Net income allocated to common shareholders - basic and diluted	$	45,771	$	34,063	$	49,513	$	73,287
Denominator:
Weighted-average common shares - basic	$	77,523	$	77,951	$	77,512	$	78,719
Dilutive potential common shares		157		164		164		162
Weighted-average common shares - diluted	$	77,680	$	78,115	$	77,676	$	78,881
Earnings per common share:
Basic	$	0.59	$	0.44	$	0.64	$	0.93
Diluted	$	0.59	$	0.44	$	0.64	$	0.93