Consolidated Statements of Cash Flows - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash flows from operating activities:
Net income	$ 89,217	$ 48,190	$ 48,837
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	3,532	3,281	2,428
Provision for loan losses	6,644	10,130	3,605
Deferred income taxes	(3,307)	(21,105)	(7,263)
Net amortization of debt securities	1,691	2,415	3,225
Amortization of intangible assets	2,503	2,609	924
Gain on sale of investment securities	(9)	(22)	(86)
Mortgage loans originated for sale	(36,229)	(138,949)	(157,129)
Proceeds from mortgage loans sold	39,310	145,836	154,993
Gain on sale of other real estate	(13)	(93)	(1,837)
Gain on state tax credits, net	(2,820)	(2,581)	(2,647)
Excess tax benefit of share-based compensation	0	0	(1,327)
Share-based compensation	3,452	3,427	3,367
Net accretion of loan discount	(1,700)	(5,609)	(11,057)
Changes in:
Accrued interest receivable	(2,001)	(158)	(2,718)
Accrued interest payable	247	(27)	476
Other assets	(677)	506	(7,739)
Other liabilities	2,354	(44,269)	41,943
Net cash provided by operating activities	108,808	45,791	82,521
Cash flows from investing activities:
Net cash paid for acquisitions and dispositions	0	4,456	0
Net increase in loans	(257,872)	(270,090)	(328,023)
Sale of debt securities, available for sale	1,451	144,076	2,493
Paydown or maturity of debt securities, available for sale	84,189	143,949	63,502
Paydown or maturity of debt securities, held to maturity	6,397	6,510	3,655
Redemption of other investments	50,274	43,207	52,279
Sale of state tax credits held for sale	14,718	15,314	18,757
Sale of other real estate	875	2,779	11,346
Payments for the purchase of:
Available for sale debt securities	(172,026)	(325,393)	(81,195)
Held to maturity debt securities	0	0	(40,529)
Other investments	(51,828)	(56,412)	(49,645)
State tax credits held for sale	(6,017)	(18,294)	(8,201)
Fixed assets	(3,035)	(2,546)	(2,496)
Net cash used in investing activities	(331,618)	(312,444)	(358,057)
Cash flows from financing activities:
Net (decrease) increase in noninterest-bearing deposit accounts	(23,189)	96,681	149,296
Net increase in interest-bearing deposit accounts	454,760	61,204	299,474
Proceeds from the issuance of subordinated notes	0	0	48,733
Proceeds from Federal Home Loan Bank advances	1,258,000	1,716,500	1,357,000
Repayments of Federal Home Loan Bank advances	(1,360,500)	(1,544,000)	(1,467,000)
Proceeds from Notes Payable	2,000	10,000	0
Repayments of Notes Payable	0	10,000	0
Net (decrease) increase in other borrowings	(32,224)	(79,417)	6,654
Cash dividends paid on common stock	(10,845)	(10,249)	(8,211)
Excess tax benefit of share-based compensation	0	0	1,327
Payments for Repurchase of Common Stock	19,387	16,636	4,889
Payments for Repurchase of Equity	(2,576)	(2,909)	(2,203)
Net cash provided by financing activities	266,039	221,174	380,181
Net increase (decrease) in cash and cash equivalents	43,229	(45,479)	104,645
Cash and cash equivalents, beginning of period	153,323	198,802	94,157
Cash and cash equivalents, end of period	196,552	153,323	198,802
Supplemental disclosures of cash flow information:
Cash paid during the period for interest	45,650	24,610	13,253
Cash paid during the period for income taxes	10,136	12,449	26,039
Noncash transactions:
Real Estate Owned, Transfer to Real Estate Owned	876	564	2,743
Sales of other real estate financed	$ 0	$ 0	$ 140
Stock Issued During Period, Shares, Acquisitions	0	141,729	0