Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
OPERATING ACTIVITIES
Net income	$ 74,364,000	$ 35,688,000	$ 23,231,000
Items not requiring (providing) cash:
Depreciation and amortization	13,654,000	7,933,000	6,127,000
Provision for loan losses	9,022,000	7,245,000	4,118,000
(Gain) loss on sale of available-for-sale securities	(307,000)	(8,000)	151,000
Net (accretion) of investment securities and assets not covered by FDIC loss share	(32,933,000)	(8,711,000)	(1,233,000)
Net amortization on borrowings	375,000
Stock-based compensation expense	4,018,000	1,423,000	1,417,000
Net accretion on assets covered by FDIC loss share	(2,709,000)	(1,497,000)	(5,878,000)
Loss (gain) on sale of premises and equipment, net of impairment	2,339,000	(4,630,000)
Deferred income taxes	13,599,000	(9,029,000)	(4,618,000)
FDIC loss share indemnification loss	7,476,000
Gain on sale of banking operation	(2,110,000)
Bank owned life insurance income	(2,680,000)	(1,843,000)	(1,319,000)
Changes in:
Interest receivable	713,000	359,000	(1,097,000)
Mortgage loans held for sale	(9,000,000)	(11,771,000)	15,873,000
Assets held in trading accounts	2,565,000	1,991,000	(2,754,000)
Other assets	5,453,000	(17,313,000)	6,047,000
Accrued interest and other liabilities	1,393,000	6,511,000	(3,032,000)
Income taxes payable	3,466,000	5,272,000	(944,000)
Net cash provided by operating activities	88,698,000	11,620,000	36,089,000
INVESTING ACTIVITIES
Net originations of loans not covered by FDIC loss share	(301,323,000)	(83,825,000)	(90,977,000)
Net collections of loans covered by FDIC loss share	23,646,000	55,361,000	78,305,000
Decrease in due from banks - time	10,879,000
Proceeds from sale of student loans		22,136,000
(Purchases) proceeds from sale of premises and equipment, net	(9,094,000)	18,762,000	(4,772,000)
Proceeds from sale of foreclosed assets held for sale	36,649,000	26,900,000	18,832,000
Proceeds from sale of foreclosed assets held for sale, covered by FDIC loss share	2,858,000	14,328,000	16,274,000
Proceeds from sale of available-for-sale securities	32,007,000	20,609,000	44,662,000
Proceeds from maturities of available-for-sale securities	435,438,000	194,423,000	165,606,000
Purchases of available-for-sale securities	(445,281,000)	(265,835,000)	(89,986,000)
Proceeds from maturities of held-to-maturity securities	281,120,000	403,186,000	112,359,000
Purchases of held-to-maturity securities	(59,486,000)	(413,020,000)	(273,924,000)
Purchases of bank owned life insurance	(12,143,000)	(7,826,000)	(7,000,000)
Settlement of FDIC loss share agreements	2,368,000
Cash received on FDIC loss share	3,980,000	15,700,000	14,530,000
Purchases of credit card loans			(10,999,000)
Cash paid on sale of banking operations, net of cash received	(68,273,000)
Cash received in business combinations, net of cash paid	197,029,000	11,343,000	35,485,000
Net cash provided by investing activities	130,374,000	12,242,000	8,395,000
FINANCING ACTIVITIES
Net change in deposits	(107,633,000)	(192,211,000)	(14,103,000)
Dividends paid on preferred stock	(257,000)
Dividends paid on common stock	(27,026,000)	(15,359,000)	(13,707,000)
Net change in other borrowed funds	(143,914,000)	(13,385,000)	(8,988,000)
Net change in federal funds purchased and securities sold under agreements to repurchase	(27,418,000)	(8,401,000)	3,809,000
Net shares issued under stock compensation plans	3,529,000	2,023,000	936,000
Repurchase of common stock			(10,848,000)
Net cash used in financing activities	(302,719,000)	(227,333,000)	(42,901,000)
(DECREASE) INCREASE IN CASH EQUIVALENTS	(83,647,000)	(203,471,000)	1,583,000
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	335,909,000	539,380,000	537,797,000
CASH AND CASH EQUIVALENTS, END OF YEAR	$ 252,262,000	$ 335,909,000	$ 539,380,000