Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net income		$ 56,712	$ 34,844
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses		4,975	2,079
Depreciation, amortization and accretion, net		10,718	10,031
Deferred income tax expense		463	4,771
Gain on sale of mortgage loans held for sale		(745)	(504)
Origination of mortgage loans held for sale		(55,391)	(79,643)
Proceeds from sale of mortgage loans held for sale		51,673	82,275
Bank owned life insurance income	[1]	(1,108)	(536)
Loss on the disposal of premises and equipment	[1]	227	28
Stock compensation expense		2,187	2,048
Excess tax benefit from share-based compensation arrangements		(530)	(1,112)
Net change in accrued interest receivable and other assets		(40,833)	(4,747)
Net change in accrued interest payable and other liabilities		15,535	(27,776)
Net cash provided by operating activities		43,883	21,758
Cash flows from investing activities:
Purchases of available for sale debt securities		(170)	(85,659)
Proceeds from sales of acquired available for sale debt securities		0	2,111
Proceeds from maturities and paydowns of available for sale debt securities		58,501	78,409
Purchases of held to maturity debt securities		0	(459,183)
Proceeds from maturities and paydowns of held to maturity debt securities		23,303	159,119
Purchases of Federal Home Loan Bank stock		(16,438)	0
Net change in non-PPP loans		(225,628)	(180,130)
Purchases of premises and equipment		(3,472)	(13,563)
Proceeds from sale or disposal of premises and equipment		411	0
Other investment activities		(506)	0
Proceeds from sales of other real estate owned		0	56
Cash from acquisition, net of cash paid		0	349,456
Net cash used in investing activities		(152,494)	(45,417)
Cash flows from financing activities:
Net change in deposits		(182,872)	(358,526)
Net change in securities sold under agreements to repurchase and federal funds purchased		7,862	18,223
Proceeds from Federal Home Loan Bank advances		1,400,000	0
Repayments of Federal Home Loan Bank advances		(1,050,000)	0
Repayment of acquired line of credit		0	(3,200)
Share repurchases related to compensation plans		(2,380)	(3,559)
Cash disbursements to non-controlling interest		0	(208)
Cash dividends paid		(17,036)	(16,394)
Net cash (used in) provided by financing activities		155,574	(363,664)
Net change in cash and cash equivalents		46,963	(387,323)
Beginning cash and cash equivalents		167,367	961,192
Ending cash and cash equivalents		214,330	573,869
Interest paid		38,125	2,147
Income taxes paid, net of refunds		17,010	7,989
Cash paid for operating lease liabilities		2,126	1,800
Supplemental non-cash activity:
Unfunded commitments in tax credit investments		49,012	6,907
Dividends payable to stockholders		183	182
Loans transferred to OREO		0	445
Premises and equipment transferred to premises held for sale		715	0
Fair value of assets acquired		0	1,403,509
Cash paid in acquisition		0	30,994
Common stock issued in acquisition		0	133,825
Non-controlling interest of acquired entity		0	3,094
Total consideration paid		0	167,913
Liabilities assumed		0	1,235,596
Small Business Administration (SBA), CARES Act, Paycheck Protection Program [Member]
Cash flows from investing activities:
Net change in PPP loans		$ 11,505	$ 103,967

[1] Outside of the scope of ASC 606.