Consolidated Statements of Cash Flows - Unaudited - USD ($)	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash Flows from Operating Activities
Net income	$ 53,833,000	$ 57,222,000
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	4,257,000	5,937,000
Depreciation and amortization	10,235,000	7,476,000
Share-based compensation expense	6,595,000	5,377,000
Deferred taxes	6,238,000	286,000
Net amortization of investment securities premiums and discounts	1,204,000	520,000
Unrealized loss recognized on equity securities	1,533,000	0
Loss (gain) on sale of investment securities	18,659,000	(8,532,000)
Impairment loss on investment securities	0	12,934,000
Gain on sale of SBA and other loans	(3,880,000)	(3,553,000)
Origination of loans held for sale	(22,978,000)	(32,343,000)
Proceeds from the sale of loans held for sale	23,936,000	31,718,000
Amortization of fair value discounts and premiums	164,000	93,000
Net (gain) loss on sales of other real estate owned	(35,000)	154,000
Valuation and other adjustments to other real estate owned	124,000	298,000
Earnings on investment in bank-owned life insurance	(5,769,000)	(5,297,000)
Increase in accrued interest receivable and other assets	(21,525,000)	(27,862,000)
Increase (decrease) in accrued interest payable and other liabilities	25,774,000	(14,106,000)
Net Cash Provided By Operating Activities	98,365,000	30,322,000
Cash Flows from Investing Activities
Proceeds from maturities, calls and principal repayments of securities available for sale	38,926,000	36,461,000
Proceeds from sale of available-for-sale securities	476,182,000	670,522,000
Purchases of investment securities available for sale	(763,242,000)	(796,594,000)
Origination of mortgage warehouse loans	(21,739,744,000)	(22,738,383,000)
Proceeds from repayments of mortgage warehouse loans	22,016,825,000	22,893,950,000
Net increase in loans, excluding mortgage warehouse loans	(20,476,000)	(921,049,000)
Proceeds from sales of loans	42,211,000	124,703,000
Purchase of loans	(347,740,000)	(262,641,000)
Purchases of bank-owned life insurance	0	(90,000,000)
Proceeds from bank-owned life insurance	529,000	1,418,000
Net proceeds from (purchases of) FHLB, Federal Reserve Bank, and other restricted stock	31,712,000	(30,203,000)
Purchases of bank premises and equipment	(1,344,000)	(1,725,000)
Proceeds from sales of other real estate owned	421,000	1,680,000
Purchase of university relationship intangible asset	(1,502,000)	0
Purchase of leased assets under operating leases	(21,849,000)	0
Net Cash Used In Investing Activities	(289,091,000)	(1,111,861,000)
Cash Flows from Financing Activities
Net increase in deposits	1,713,572,000	293,301,000
Net (decrease) increase in short-term borrowed funds from the FHLB	(776,860,000)	593,543,000
Net (decrease) increase in federal funds purchased	(155,000,000)	64,000,000
(Repayments of) proceeds from issuance of long-term debt	(63,250,000)	98,564,000
Preferred stock dividends paid	(10,844,000)	(10,844,000)
Exercise of warrants	112,000	557,000
Payments of employee taxes withheld from share-based awards	(711,000)	(4,923,000)
Proceeds from issuance of common stock	3,418,000	2,112,000
Net Cash Provided By Financing Activities	710,437,000	1,036,310,000
Net Increase (Decrease) in Cash and Cash Equivalents	519,711,000	(45,229,000)
Cash and Cash Equivalents – Beginning	146,323,000	264,709,000
Cash and Cash Equivalents – Ending	666,034,000	219,480,000
Supplementary Cash Flows Information:
Interest paid	114,973,000	70,706,000
Income taxes paid	4,156,000	31,545,000
Non-cash items:
Transfer of loans to other real estate owned	234,000	83,000
Transfer of loans held for investment to held for sale	0	150,638,000
Transfer of loans held for sale to held for investment	$ 129,691,000	$ 0