Consolidated statements of cash flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net income	$ 19,588	$ 19,754
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation expense	1,172	1,106
Amortization of core deposit and other intangibles	729	853
Capitalization of mortgage servicing rights	(8,720)	(13,510)
Net change in fair value of mortgage servicing rights	4,358	(3,543)
Stock-based compensation expense	1,638	1,958
Provision for loan losses	1,391	317
Provision for mortgage loan repurchases	59	186
Accretion of yield on purchased loans	(1,831)	(1,687)
Accretion of discounts and amortization of premiums on securities, net	614	697
(Gain) loss from securities, net	(43)	47
Originations of loans held for sale	(932,125)	(1,617,103)
Repurchases of loans held for sale	(5,957)	0
Proceeds from sale of loans held for sale	986,454	1,707,527
Gain on sale and change in fair value of loans held for sale	(18,151)	(23,391)
Net loss or write-downs of other real estate owned	39	186
Gain on other assets	(191)	(68)
Provision for deferred income taxes	(4,219)	5,482
Changes in:
Other assets and interest receivable	(22,511)	(4,759)
Accrued expenses and other liabilities	10,133	(26,207)
Net cash provided by operating activities	32,427	47,845
Activity in available-for-sale securities:
Sales	1,758	221
Maturities, prepayments and calls	20,814	16,503
Purchases	(24,196)	(81,990)
Net increase in loans	(118,358)	(74,928)
Proceeds from sale of mortgage servicing rights	29,160	0
Purchases of premises and equipment	(911)	(704)
Proceeds from the sale of premises and equipment	284	0
Proceeds from the sale of other real estate owned	716	1,432
Net cash used in investing activities	(90,733)	(139,466)
Cash flows from financing activities:
Net increase in demand deposits	107,959	83,076
Net increase in time deposits	23,515	18,680
Net increase (decrease) in borrowings	1,402	(54,578)
Share based compensation witholding obligation	(2,373)	(2,277)
Net proceeds from sale of common stock	364	669
Dividends paid	(2,503)	0
Net cash provided by financing activities	128,364	45,570
Net change in cash and cash equivalents	70,058	(46,051)
Cash and cash equivalents at beginning of the period	125,356	119,751
Cash and cash equivalents at end of the period	195,414	73,700
Supplemental cash flow information:
Interest paid	10,820	6,066
Taxes paid	77	31
Supplemental noncash disclosures:
Transfers from loans to other real estate owned	1,106	630
Transfers from other real estate owned to loans	166	120
Transfers from loans held for sale to loans	540	1,599
Trade date payable - securities	2,524	3,912
Dividends declared not paid on restricted stock units	84	0
Adjustment to retained earnings for adoption of new accounting standards	(1,309)	(109)
Right-of-use assets obtained in exchange for new operating lease liabilities	33,819	0
GNMA
Supplemental noncash disclosures:
Derecognition of rebooked GNMA delinquent loans	$ 0	$ 43,035