Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 82,152	$ 43,034
Adjustments to reconcile net income to net cash provided by (used in) operating activities
Provision for loan and lease losses	4,682	6,209
Provision (reversal) for loan repurchases	(451)	2,023
Net revenue on mortgage banking activities	(127,638)	(114,351)
Net gain on sale of loans	(15,405)	(22,047)
Net amortization of premiums and discounts on securities	1,061	1,385
Depreciation on premises and equipment	8,510	6,600
Amortization of intangibles	3,823	4,490
Amortization of debt issuance cost	480	428
Stock option compensation expense	400	357
Stock award compensation expense	8,110	6,285
Stock appreciation right compensation expense	17	188
Bank owned life insurance income	(1,738)	(475)
Impairment on intangible assets	0	258
Debt redemption costs	2,737	0
Net gain on sale of securities available-for-sale	(30,100)	(1,748)
Gain on sale of building	0	(9,919)
Gain on sale of branches	0	163
Gain on sale of subsidiary	(3,694)	0
Gain on sale of mortgage servicing rights	(2)	0
Loss (gain) on sale of other real estate owned	49	(23)
Loss on investments in alternative energy partnerships, net	17,660	0
Deferred income tax expense	5,197	1,916
Loss on sale or disposal of property and equipment	78	58
Loss from change of fair value and runoff on mortgage servicing rights	22,908	8,417
Increase in valuation allowances on other real estate owned	25	38
Repurchase of mortgage loans	(29,458)	(12,589)
Originations of loans held-for-sale from mortgage banking	(3,824,562)	(3,404,030)
Originations of other loans held-for-sale	(545,920)	(585,547)
Proceeds from sales of and principal collected on loans held-for-sale from mortgage banking	3,853,406	3,421,045
Proceeds from sales of and principal collected on other loans held-for-sale	493,346	705,036
Change in deferred loan fees	(663)	468
Net amortization of premiums and discounts on purchased loans	(31,029)	(21,507)
Change in accrued interest receivable	(9,216)	(4,593)
Change in other assets	(49,580)	(14,460)
Change in accrued interest payable and other liabilities	15,958	23,613
Net cash provided by (used in) operating activities	(148,857)	40,396
Cash flows from investing activities:
Proceeds from sales of securities available-for-sale	3,783,965	403,206
Proceeds from maturities and calls of securities available-for-sale	0	687
Proceeds from principal repayments of securities available-for-sale	72,390	88,327
Purchases of securities available-for-sale	(4,856,401)	(837,520)
Purchases of securities held-to-maturity	0	(529,534)
Purchases of bank owned life insurance	0	(80,000)
Net cash used in branch sales	0	(46,731)
Proceeds from sale of subsidiary	259	0
Loan and lease originations and principal collections, net	(1,448,427)	(360,253)
Purchase of loans and leases	(179,897)	(227,175)
Redemption of Federal Home Loan Bank stock	20,965	17,163
Purchase of Federal Home Loan Bank and other bank stock	(31,125)	(15,565)
Proceeds from sale of loans	276,264	389,944
Proceeds from sale of other real estate owned	1,592	908
Proceeds from sale of mortgage servicing rights	5	5,862
Proceeds from sale of premises and equipment	0	52,192
Additions to premises and equipment	(30,847)	(7,950)
Payments of capital lease obligations	(728)	(682)
Investments in alternative energy partnerships	(41,572)	0
Net cash used in investing activities	(2,433,557)	(1,147,121)
Cash flows from financing activities:
Net increase in deposits	2,775,234	796,760
Net increase (decrease) in short-term Federal Home Loan Bank advances	(110,000)	62,000
Repayment of long-term Federal Home Loan Bank advances	(50,000)	(265,000)
Proceeds from long-term Federal Home Loan Bank advances	0	400,000
Net increase in other borrowings	49,903	0
Net proceeds from issuance of common stock	175,090	0
Net proceeds from issuance of preferred stock	120,255	110,873
Redemption of preferred stock	(42,000)	0
Net proceeds from issuance of long term debt	0	172,304
Payment of amortizing debt	(3,773)	(3,503)
Redemption of long term debt	(84,750)	0
Proceeds from exercise of stock options	0	465
Cash settlement of stock options	(359)	0
Dividend equivalents paid on stock appreciation rights	(556)	(516)
Dividends paid on preferred stock	(14,518)	(6,416)
Dividends paid on common stock	(15,633)	(12,478)
Net cash provided by financing activities	2,798,893	1,254,489
Net change in cash and cash equivalents	216,479	147,764
Cash and cash equivalents at beginning of period	156,124	231,199
Cash and cash equivalents at end of period	372,603	378,963
Supplemental cash flow information
Interest paid on deposits and borrowed funds	43,968	35,079
Income taxes paid	36,647	24,460
Income taxes refunds received	1	18
Supplemental disclosure of non-cash activities
Transfer from loans to other real estate owned, net	844	534
Transfer of loans held-for-investment to loans held-for-sale, net of transfer of $0 from allowance for loan and lease losses for the nine months ended September 30, 2016 and 2015	161,601	48,757
Transfer of loans held-for-sale to loans held-for-investment	7,115	482,851
Equipment acquired under capital leases	16	34
Due on unsettled securities purchases	$ 61,766	$ 0