CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Operating activities:
Net income	$ 41,946	$ 40,106
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	3,830	4,001
Amortization of intangible assets	4,130	4,798
Net accretion on securities, loans and borrowings	(1,944)	(2,214)
Stock-based compensation	1,391	1,715
Provision for loan losses	2,422	3,679
Amortization of mortgage servicing rights	98	117
Unrealized gain on equity securities	(31)	0
Income from bank-owned life insurance policies	(391)	(388)
Net loss (gain) on sale of loans and other assets	22	(80)
Change in other assets and other liabilities	(16,864)	9,253
Net cash provided by operating activities	34,609	60,987
Investing activities:
Proceeds from maturities, calls, and paydowns of available-for-sale investment securities	52,520	27,363
Proceeds from maturities and redemptions of equity and other investment securities	2,460	4,960
Purchases of available-for-sale investment securities	(13,388)	(23,434)
Purchases of equity and other securities	(24)	(21)
Net decrease in loans	11,847	25,900
Cash paid for acquisitions, net of cash acquired of $0 and $16, respectively	(1,200)	(1,464)
Purchases of premises and equipment, net	(1,227)	(1,556)
Real estate limited partnership investments	(564)	(79)
Net cash provided by investing activities	50,424	31,669
Financing activities:
Net increase in deposits	297,291	326,672
Net decrease in borrowings	(63,910)	(81,338)
Issuance of common stock	(844)	570
Purchases of treasury stock	(79)	(81)
Sales of treasury stock	1,885	2,546
Increase in deferred compensation arrangements	79	81
Cash dividends paid	(19,806)	(17,281)
Withholding taxes paid on share-based compensation	(3,119)	(964)
Net cash provided by financing activities	211,497	230,205
Change in cash and cash equivalents	296,530	322,861
Cash and cash equivalents at beginning of period	211,834	221,038
Cash and cash equivalents at end of period	508,364	543,899
Supplemental disclosures of cash flow information:
Cash paid for interest	5,684	3,757
Cash paid for income taxes	4,486	564
Supplemental disclosures of noncash financing and investing activities:
Dividends declared and unpaid	19,578	17,438
Transfers from loans to other real estate	412	942
Acquisitions:
Common stock issued	0	0
Fair value of assets acquired, excluding acquired cash and intangibles	0	27
Fair value of liabilities assumed	$ 0	$ 31