CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating activities:
Net income	$ 54,089	$ 86,860
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	6,544	7,373
Amortization of intangible assets	7,372	7,583
Net amortization (accretion) on securities, loans and borrowings	1,749	(9,662)
Stock-based compensation	4,194	4,190
Gain on debt extinguishment	(242)	0
Provision for credit losses	4,252	6,944
Amortization of mortgage servicing rights	452	299
Loss on sales of investment securities	52,329	0
Unrealized loss on equity securities	50	20
Income from bank-owned life insurance policies	(1,166)	(944)
Net gain on sale of assets	(1,061)	(305)
Change in other assets and liabilities	(9,706)	(3,443)
Net cash provided by operating activities	118,856	98,915
Investing activities:
Proceeds from maturities, calls, and paydowns of available-for-sale investment securities	394,452	86,423
Proceeds from maturities, calls, and paydowns of held-to-maturity investment securities	24	0
Proceeds from maturities and redemptions of equity and other investment securities	23,823	464
Proceeds from sales of available-for-sale investment securities	733,789	0
Purchases of available-for-sale investment securities	0	(1,348,400)
Purchases of held-to-maturity investment securities	(9,778)	0
Purchases of equity and other securities	(3,540)	(313)
Net increase in loans	(373,950)	(335,796)
Cash (paid) received for acquisitions, net of cash acquired of $0 and $84,988, respectively	(6,376)	345
Proceeds from sales of premises, equipment and other assets	4,367	483
Purchases of premises and equipment	(6,941)	(5,462)
Real estate limited partnership investments	0	(247)
Net cash provided by (used in) investing activities	755,870	(1,602,503)
Financing activities:
Net decrease in deposits	(140,522)	(75,691)
Net (decrease) increase in overnight borrowings	(534,400)	66,000
Net decrease in securities sold under agreement to repurchase, short-term	(113,183)	(100,965)
Net decrease in other Federal Home Loan Bank borrowings	(2,239)	(33)
Redemption of subordinated notes payable	(3,000)	0
Proceeds from issuance of common stock	664	799
Purchases of treasury stock	(20,679)	(16,498)
Increase in deferred compensation arrangements	111	120
Cash dividends paid	(47,442)	(46,453)
Withholding taxes paid on share-based compensation	(1,153)	(1,127)
Net cash used in financing activities	(861,843)	(173,848)
Change in cash and cash equivalents	12,883	(1,677,436)
Cash and cash equivalents at beginning of period	209,896	1,875,064
Cash and cash equivalents at end of period	222,779	197,628
Supplemental disclosures of cash flow information:
Cash paid for interest	36,408	5,967
Cash paid for income taxes	18,478	25,247
Supplemental disclosures of noncash financing and investing activities:
Dividends declared and unpaid	23,735	23,264
Transfers from loans to other real estate	232	303
Transfers from premises and equipment, net to other assets	1,948	0
Acquisitions:
Fair value of assets acquired, excluding acquired cash and intangibles	60	490,623
Fair value of liabilities assumed	$ 9	$ 543,507