Unaudited Quarterly Financial Data (Condensed) (Tables)

12 Months Ended

Dec. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Summarized unaudited quarterly financial data

Summarized unaudited quarterly financial data is as follows:

	Quarters ended 2016
(Dollars in thousands, except per share data)	March 31		June 30	September 30	December 31
Interest income	$	84,381	86,069	85,944	87,759
Interest expense	7,675		7,424	7,318	7,214
Net interest income	76,706		78,645	78,626	80,545
Provision for loan losses	568		—	626	1,139
Net interest income after provision for loan losses	76,138		78,645	78,000	79,406
Non-interest income	24,252		26,759	28,293	28,014
Non-interest expense	62,356		64,461	65,180	66,717
Income before income taxes	38,034		40,943	41,113	40,703
Federal and state income tax expense	9,352		10,492	10,156	9,662
Net income	$	28,682	30,451	30,957	31,041
Basic earnings per share	$	0.38	0.40	0.40	0.41
Diluted earnings per share	$	0.38	0.40	0.40	0.41

	Quarters ended 2015
(Dollars in thousands, except per share data)	March 31		June 30	September 30	December 31
Interest income	$	77,486	78,617	80,367	83,211
Interest expense	7,382		7,369	7,309	7,215
Net interest income	70,104		71,248	73,058	75,996
Provision for loan losses	765		282	826	411
Net interest income after provision for loan losses	69,339		70,966	72,232	75,585
Non-interest income	22,693		25,802	25,799	24,467
Non-interest expense	55,497		59,945	59,112	62,203
Income before income taxes	36,535		36,823	38,919	37,849
Federal and state income tax expense	8,865		7,488	9,305	8,341
Net income	$	27,670	29,335	29,614	29,508
Basic earnings per share	$	0.37	0.39	0.39	0.39
Diluted earnings per share	$	0.37	0.39	0.39	0.39