Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash flows from operating activities
Net income	$ 34,509	$ 39,427
Adjustments to reconcile net income to net cash provided (used) by operating activities:
Depreciation and amortization	5,405	5,265
Provision for (recovery of) loan and lease credit losses	1,836	(873)
Amortization of premium on securities, net of accretion	1,421	1,817
Deferred tax expense (benefit)	6,775	(3,984)
Originations of loans held for sale	(222,557)	(253,588)
Proceeds from sales of loans held for sale	349,364	182,685
Net gains on sale of loans held for sale	(20,977)	(11,929)
Net loss on sale of foreclosed assets	17	24
Net gain on loans accounted for under fair value option	(516)	(4,218)
Net increase in servicing assets	(2,712)	(3,826)
Net gain on disposal of long-lived asset		(114)
Net gain on disposal of property and equipment		(48)
Impairment on premises and equipment, net		904
Equity method investments (income) loss	2,124	1,157
Equity security investments (gains) losses, net	44	(105)
Renewable energy tax credit investment impairment		3,127
Stock option based compensation expense	391	344
Restricted stock expense	4,563	4,670
Stock based compensation excess tax benefit	1,119	5,152
Changes in assets and liabilities:
Lease right-of-use assets and liabilities, net	(12)	(1)
Other assets	(3,095)	2,699
Other liabilities	(1,260)	(5,406)
Net cash provided (used) by operating activities	156,439	(36,821)
Cash flows from investing activities
Purchases of securities available-for-sale	(37,837)	(108,223)
Proceeds from sales, maturities, calls, and principal paydown of securities available-for-sale	47,297	65,039
Proceeds from SBA reimbursement/sale of foreclosed assets, net	333	152
Maturities of certificates of deposits with other banks	500
Loan and lease originations and principal collections, net	(243,463)	(121,814)
Proceeds from sale of long-lived asset		8,988
Proceeds from sale of premises and equipment		84
Purchases of premises and equipment, net	(20,036)	(674)
Net cash used by investing activities	(253,206)	(156,448)
Cash flows from financing activities
Net increase in deposits	525,119	603,176
Proceeds from borrowings	12,026	498,666
Repayment of borrowings	(133,404)	(580,291)
Stock option exercises	719	1,213
Employee stock purchase program	534	296
Withholding cash issued in lieu of restricted stock and other	(2,894)	(11,287)
Shareholder dividend distributions	(1,312)	(1,282)
Net cash provided by financing activities	400,788	510,491
Net increase in cash and cash equivalents	304,021	317,222
Cash and cash equivalents, beginning	203,750	318,320
Cash and cash equivalents, ending	507,771	635,542
Supplemental disclosures of cash flow information
Interest paid	15,263	18,469
Income tax paid, net	8	354
Supplemental disclosures of noncash operating, investing, and financing activities
Unrealized holding losses on available-for-sale securities, net of taxes	(38,452)	(12,379)
Transfers from loans and leases to foreclosed real estate and other repossessions or SBA receivable	6,692	2,246
Net transfers between foreclosed real estate and SBA receivable	72	196
Transfer of loans held for sale to loans and leases held for investment	70,649	176,285
Transfer of loans and leases held for investment to loans held for sale	110,452	24,260
Transfer from retained earnings to other assets for pro rata portion of equity method investee stock compensation expense	136	1,508
Recording of secured borrowing		5,493
Equity method investment commitments	10,971
Equity security investment commitments	$ 500	$ 1,500