Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net income	$ 27,913	$ 23,508
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization of intangibles	2,598	3,024
Provision for loan losses	5,400	1,500
Deferred tax expense	2,015	2,632
Income on Bank-owned life insurance	(1,264)	(1,389)
Net amortization of premiums and discounts on securities	2,279	2,450
Accretion of net deferred loan fees	(1,286)	(1,146)
Amortization of premiums on purchased loans, net	200	219
Net increase in loans originated for sale	(4,117)	(990)
Proceeds from sales of loans originated for sale	4,528	89
Proceeds from sales and paydowns of foreclosed assets	466	2,167
ESOP expense	1,085	1,095
Allocation of stock award shares	1,025	541
Allocation of stock options	45	44
Net gain on sale of loans	(411)	(89)
Net gain on securities transactions	(1)	0
Net gain on sale of foreclosed assets	(181)	(288)
(Increase) decrease in accrued interest receivable	(924)	413
Decrease in other assets	1,146	2,620
Decrease in other liabilities	(8,309)	(12,007)
Net cash provided by operating activities	32,207	24,393
Cash flows from investing activities:
Proceeds from maturities, calls and paydowns of held to maturity debt securities	21,934	15,668
Purchases of held to maturity debt securities	(11,881)	(17,297)
Proceeds from maturities and paydowns of available for sale debt securities	55,279	48,819
Purchases of available for sale debt securities	(72,154)	(57,015)
Proceeds from redemption of Federal Home Loan Bank stock	39,929	32,311
Purchases of Federal Home Loan Bank stock	(33,342)	(33,221)
Net decrease in loans	34,994	5,626
Purchases of premises and equipment	(502)	(589)
Net cash provided by (used in) investing activities	34,257	(5,698)
Cash flows from financing activities:
Net increase (decrease) in deposits	42,417	(23,759)
Increase in mortgage escrow deposits	1,061	1,839
Cash dividends paid to stockholders	(13,638)	(12,629)
Shares issued through the dividend reinvestment plan	419	475
Purchases of treasury stock	0	(443)
Purchase of employee restricted shares to fund statutory tax withholding	(1,792)	(703)
Stock options exercised	175	2,508
Proceeds from long-term borrowings	265,000	70,420
Payments on long-term borrowings	(135,810)	(91,009)
Net (decrease) increase in short-term borrowings	(281,616)	48,403
Net cash used in financing activities	(123,784)	(4,898)
Net (decrease) increase in cash and cash equivalents	(57,320)	13,797
Cash and cash equivalents at beginning of period	190,834	144,297
Cash and cash equivalents at end of period	133,514	158,094
Cash paid during the period for:
Interest on deposits and borrowings	12,972	10,944
Income taxes	3,619	105
Non-cash investing activities:
Transfer of loans receivable to foreclosed assets	$ 673	$ 1,708