CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Operating activities:
Net income	$ 26,257	$ 24,403
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	3,669	3,556
Amortization of intangible assets	2,768	1,442
Net accretion on securities, loans and borrowings	(406)	(911)
Stock-based compensation	1,410	1,219
Provision for loan losses	1,828	1,341
Amortization of mortgage servicing rights	126	131
Income from bank-owned life insurance policies	(368)	(355)
Net gain on sale of loans and other assets	(53)	(68)
Change in other assets and liabilities	7,430	(3,454)
Net cash provided by operating activities	42,661	27,304
Investing activities:
Proceeds from maturities of available-for-sale investment securities	33,479	18,894
Proceeds from maturities of other investment securities	8,709	12,297
Purchases of available-for-sale investment securities	(16,784)	(12,255)
Purchases of other securities	(505)	(4,612)
Net change in loans	12,197	(22,031)
Cash paid for acquisition, net of cash acquired of $11,063 and $0, respectively	(63,517)	(575)
Purchases of premises and equipment, net	(2,088)	(2,639)
Net cash used in investing activities	(28,509)	(10,921)
Financing activities:
Net change in deposits	260,923	245,588
Net change in borrowings	(146,200)	(267,600)
Issuance of common stock	1,809	932
Sales of treasury stock	2,151	5,022
Cash dividends paid	(14,186)	(13,605)
Withholding taxes paid on share-based compensation	(1,320)	(1,417)
Net cash provided by/(used in) financing activities	103,177	(31,080)
Change in cash and cash equivalents	117,329	(14,697)
Cash and cash equivalents at beginning of period	173,857	153,210
Cash and cash equivalents at end of period	291,186	138,513
Supplemental disclosures of cash flow information:
Cash paid for interest	2,707	2,863
Cash paid for income taxes	9,044	7,065
Supplemental disclosures of noncash financing and investing activities:
Dividends declared and unpaid	14,773	13,610
Transfers from loans to other real estate	920	390
Acquisitions:
Common stock issued	78,483	0
Fair value of assets acquired, excluding acquired cash and intangibles	31,599	0
Fair value of liabilities assumed	$ 30,500	$ 0