CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 68,432	$ 45,925	$ 46,481
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	1,550	2,600	5,650
Depreciation of premises and equipment	3,282	3,454	3,651
Net amortization of premiums and discounts on securities and loans	2,865	3,426	2,779
Amortization of intangibles	979	1,035	1,284
Goodwill impairment	0	150	0
Share–based compensation	2,602	2,577	2,190
Tax benefit from stock option exercises and other equity awards	496	508	1,016
Deferred income tax (benefit) expense	(63)	5,687	868
Income from bank-owned life insurance	(2,196)	(2,161)	(2,659)
Net gains on loan sales and commissions on loans originated for others, including fair value adjustments	(9,749)	(10,991)	(13,137)
Net gain on sale of portfolio loans	0	0	(135)
Proceeds from sales of loans	391,960	472,556	551,788
Loans originated for sale	(378,896)	(461,262)	(532,950)
Change in fair value of contingent consideration liability	(187)	(643)	(898)
(Increase) decrease in other assets	(7,456)	(8,794)	984
Increase (decrease) in other liabilities	9,257	5,318	(7,163)
Net cash provided by operating activities	82,876	59,385	59,749
Cash flows from investing activities:
Purchases of mortgage-backed securities available for sale	(175,539)	(89,194)	(431,662)
Purchases of other investment securities available for sale	(76,264)	(59,940)	(121,679)
Maturities and principal payments of mortgage-backed securities available for sale	83,197	84,381	65,673
Maturities and principal payments of other investment securities available for sale	7,301	22,071	108,256
Maturities and principal payments of mortgage-backed securities held to maturity	2,029	2,950	4,193
(Purchases) remittance of Federal Home Loan Bank stock	(5,551)	2,612	(18,813)
Net increase in loans	(306,299)	(120,582)	(112,966)
Proceeds from sale of portfolio loans	0	0	510
Purchases of loans	(1,780)	(20,278)	(113,562)
Proceeds from the sale of property acquired through foreclosure or repossession	49	1,053	731
Purchases of premises and equipment	(3,974)	(2,779)	(3,112)
Purchases of bank-owned life insurance	(5,000)	0	(5,000)
Proceeds from bank-owned life insurance	0	0	2,054
Net cash used in investing activities	(481,831)	(179,706)	(625,377)
Cash flows from financing activities:
Net increase in deposits	281,341	178,955	129,497
Proceeds from Federal Home Loan Bank advances	2,040,000	1,352,501	1,428,750
Repayment of Federal Home Loan Bank advances	(1,880,634)	(1,410,075)	(958,793)
Payment of contingent consideration liability	(1,217)	0	0
Proceeds from stock option exercises and issuance of other equity awards, net of awards surrendered	(671)	366	977
Cash dividends paid	(29,312)	(26,300)	(24,637)
Net cash provided by financing activities	409,507	95,447	575,794
Net increase (decrease) in cash and cash equivalents	10,552	(24,874)	10,166
Cash and cash equivalents at beginning of year	82,923	107,797	97,631
Cash and cash equivalents at end of year	93,475	82,923	107,797
Noncash Investing and Financing Activities:
Loans charged-off	1,187	2,462	7,012
Loans transferred to property acquired through foreclosure or repossession	3,074	576	1,075
Supplemental Disclosures:
Interest payments	41,285	29,687	22,267
Income tax payments	$ 17,148	$ 25,988	$ 19,822