Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
NET EARNINGS	$ 26,599	$ 25,696
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	2,905	2,805
PROVISION FOR LOAN LOSSES	1,950	2,328
Securities premium amortization (discount accretion), net	7,836	6,948
Gain on sale of assets, net	(48)	(591)
Change in loans held-for-sale	13,269	16,535
Change in other assets	5,685	10,704
Change in other liabilities	8,765	7,580
Total adjustments	40,362	46,309
Net cash provided by operating activities	66,961	72,005
CASH FLOWS FROM INVESTING ACTIVITIES:
Net decrease in interest-bearing time deposits in banks		1,068
Activity in available-for-sale securities:
Sales	6,180	553
Maturities	510,416	86,258
Purchases	(683,386)	(69,605)
Activity in held-to-maturity securities-maturities	8	132
Net increase in loans	(17,029)	33,772
Purchases of bank premises and equipment and other assets	(3,888)	(5,447)
Proceeds from sale of other assets	343	480
Net cash provided by (used in) investing activities	(187,356)	47,211
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase (decrease) in noninterest-bearing deposits	109,887	(91,682)
Net decrease in interest-bearing deposits	73,542	(34,681)
Net decrease in borrowings	(85,506)	(90,335)
Common stock transactions:
Proceeds from stock issuances	563	802
Dividends paid	(11,898)	(10,558)
Net cash provided by (used in) financing activities	86,588	(226,454)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(33,807)	(107,238)
CASH AND CASH EQUIVALENTS, beginning of period	256,486	272,886
CASH AND CASH EQUIVALENTS, end of period	222,679	165,648
SUPPLEMENTAL INFORMATION AND NONCASH TRANSACTIONS:
Interest paid	1,822	1,298
Federal income tax paid	0	0
Transfer of loans and bank premises to other real estate owned	1,082	946
Investment securities purchased but not settled	$ 1,640	$ 26,452