Consolidated Statements of Cash Flow (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 98,361	$ 101,891	$ 74,496
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred income tax expense	7,748	6,421	2,000
Amortization of investment premiums, net	32,663	45,082	36,086
Gain on sale of investment securities, net	(209)	(4,023)	(7,735)
Other-than-temporary impairment on investment securities held to maturity	0	155	359
(Gain) loss on sale of non-covered other real estate owned	(335)	2,349	1,743
Gain on sale of covered other real estate owned	(577)	(1,236)	(1,228)
Valuation adjustment on non-covered other real estate owned	1,448	6,896	8,947
Valuation adjustment on covered other real estate owned	712	4,646	8,709
Provision for non-covered loan and lease losses	16,829	21,796	46,220
(Recapture of) provision for covered loan losses	(6,113)	7,405	16,141
Proceeds from bank owned life insurance	1,173	1,870	818
Change in cash surrender value of bank owned life insurance	(4,280)	(3,145)	(3,212)
Change in FDIC indemnification asset	25,549	15,234	6,168
Depreciation, amortization and accretion	18,267	16,040	13,151
Increase in mortgage servicing rights	(17,963)	(17,710)	(6,720)
Change in mortgage servicing rights carried at fair value	(2,374)	8,466	2,990
Change in junior subordinated debentures carried at fair value	2,193	2,175	2,217
Stock-based compensation	5,017	4,041	3,785
Net (increase) decrease in trading account assets	(2,211)	(1,438)	715
Gain on sale of loans	(65,644)	(91,945)	(26,838)
Change in loans held for sale carried at fair value	14,503	(13,965)	(3,435)
Origination of loans held for sale	(1,649,911)	(2,022,195)	(821,744)
Proceeds from sales of loans held for sale	1,913,776	1,910,071	828,952
Excess tax benefits from the exercise of stock options	(65)	(52)	(6)
Change in other assets and liabilities:
Net decrease (increase) in other assets	32,129	5,401	(15,404)
Net (decrease) increase in other liabilities	(7,589)	22,255	15,177
Net cash provided by operating activities	413,097	26,485	182,352
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of investment securities available for sale	(51,191)	(994,574)	(1,190,686)
Payments to Acquire Held-to-maturity Securities	(2,126)	(931)	(1,573)
Proceeds from investment securities available for sale	803,866	1,481,600	927,276
Proceeds from investment securities held to maturity	1,353	1,304	1,637
Redemption of restricted equity securities	2,758	1,629	1,894
Net non-covered loan and lease originations	(484,933)	(587,396)	(327,032)
Net covered loan and lease paydowns	101,861	114,815	119,772
Proceeds from sales of non-covered loans	60,298	14,242	11,185
Proceeds from insurance settlement on loss of property	575	1,425	0
Proceeds from fee on termination of merger transaction	0	1,600	0
Proceeds from disposals of furniture and equipment	410	2,029	921
Purchases of premises and equipment	(33,995)	(22,817)	(33,974)
Net proceeds from FDIC indemnification asset	5,332	29,478	54,881
Proceeds from sales of non-covered other real estate owned	15,830	27,093	35,340
Proceeds from sales of covered other real estate owned	10,692	12,694	17,615
Payments to Acquire Businesses, Net of Cash Acquired	(149,658)	39,328	0
Net cash used by investing activities	281,072	121,519	(382,744)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net decrease in deposit liabilities	(261,184)	(107,445)	(196,063)
Net increase in securities sold under agreements to repurchase	87,807	12,470	50,846
Repayment of term debt	(211,727)	(55,404)	(4,993)
Repayment of junior subordinated debentures	(8,764)	0	0
Dividends paid on common stock	(50,768)	(46,201)	(25,317)
Excess tax benefits from stock based compensation	65	52	6
Proceeds from exercise of stock options	6,398	981	308
Repurchases and retirement of common stock	(9,360)	(7,436)	(29,754)
Net cash used by financing activities	(447,533)	(202,983)	(204,967)
Net increase (decrease) in cash and cash equivalents	246,636	(54,979)	(405,359)
Cash and cash equivalents, beginning of year	543,787	598,766	1,004,125
Cash and cash equivalents, end of year	790,423	543,787	598,766
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Interest	40,826	52,198	78,690
Income taxes	41,993	44,350	47,608
SUPPLEMENTAL DISCLOSURE OF NONCASH INVESTING AND FINANCING ACTIVITIES:
Change in unrealized losses on investment securities available for sale, net of taxes	(29,378)	(9,616)	8,620
Change in unrealized losses on investment securities held to maturity related to factors other than credit, net of taxes	56	188	209
Cash dividend declared on common stock and payable after period-end	16,936	0	7,890
Transfer of non-covered loans to non-covered other real estate owned	21,638	17,699	47,414
Transfer of covered loans to covered other real estate owned	2,555	6,987	15,271
Transfer of covered loans to non-covered loans	14,783	16,166	12,263
Transfer from FDIC indemnification asset to due from FDIC and other	4,075	23,057	49,156
Receivable from sales of noncovered other real estate owned and loans	0	0	1,100
Receivable from sales of covered other real estate owned	0	0	547
Assets acquired	376,071	317,751	0
Liabilities assumed	$ 219,961	$ 317,751	$ 0