Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating activities:
Net income	$ 70,791	$ 81,145	$ 35,903
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provision (credit) for loan losses	(3,990)	6,340	(900)
Depreciation, amortization, accretion	6,048	5,608	4,698
Deferred income taxes	1,378	(2,620)	639
Stock based compensation	745	716	1,067
Origination of mortgage servicing rights	(5,778)	(13,406)	(354)
Proceeds on sales of mortgage servicing rights	12,448	6,985	0
Gain on sale of loans held for sale	(193,399)	(245,358)	(128,928)
Loans originated for sale	(4,198,139)	(4,332,028)	(2,853,222)
Proceeds on sales of loans originated for sale	4,480,804	4,395,505	2,903,643
Gain on death benefit on bank owned life insurance	0	(1,456)	0
Decrease (increase) in accrued interest receivable	944	387	(7)
Increase in cash surrender value of life insurance	(1,615)	(1,905)	(1,935)
Decrease (increase) in derivative assets	6,688	(9,222)	(179)
(Decrease) increase in accrued interest on deposits and borrowings	(178)	(422)	164
(Increase) decrease in prepaid income tax	(2,558)	113	330
Legal settlement	(4,250)	4,250	0
(Decrease) increase in derivative liabilities	(5,140)	5,140	(1,116)
Net gain on real estate owned	(12)	(107)	(304)
Gain on sale of mortgage servicing rights	(4,032)	(600)	0
Change in other assets and other liabilities, net	(6,301)	7,353	282
Net cash provided by (used in) operating activities	154,454	(93,582)	(40,219)
Investing activities:
Net decrease (increase) in loans receivable	170,297	12,353	(9,896)
Purchases of:
FHLB stock	0	(5,570)	(8,100)
Debt securities	0	(10,125)	0
Mortgage related securities	(73,687)	(19,372)	(28,860)
Premises and equipment, net	(778)	(1,225)	(3,114)
Bank owned life insurance	(180)	(180)	(180)
Proceeds from:
Principal repayments on mortgage-related securities	40,445	45,254	31,944
Maturities of debt securities	9,055	5,290	8,080
Sales of FHLB stock	2,282	0	6,300
Death benefit from bank owned life insurance	0	9,633	0
Sales of real estate owned	183	1,133	2,674
Net cash provided by (used in) investing activities	147,617	37,191	(1,152)
Financing activities:
Net increase in deposits	48,516	117,094	29,281
Net change in short term borrowings	(30,947)	24,512	8,516
Repayment of long term debt	0	0	(125,000)
Proceeds from long term debt	0	0	165,000
Increase (decrease) in advance payments by borrowers for taxes	572	(690)	(159)
Cash dividends on common stock	(30,388)	(31,520)	(25,960)
Proceeds from stock option exercises	2,307	3,704	659
Purchase of common stock returned to authorized but unissued	(10,176)	(36,242)	(22,767)
Net cash (used in) provided by financing activities	(20,116)	76,858	29,570
Increase (decrease) in cash and cash equivalents	281,955	20,467	(11,801)
Cash and cash equivalents at beginning of year	94,767	74,300	86,101
Cash and cash equivalents at end of year	376,722	94,767	74,300
Cash paid or credited during the period for:
Income tax payments	22,663	29,478	10,703
Interest payments	14,546	25,406	27,380
Noncash investing activities:
Loans receivable transferred to other real estate	0	637	1,052
Dividends declared but not paid in other liabilities	$ 17,525	$ 5,232	$ 3,501