Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash Flows from Operating Activities
Net income	$ 28,998	$ 29,064
Adjustments to reconcile net income to net cash provided by/(used in) operating activities:
Credit for loan losses		(4,000)
Provision/(credit) for losses on other real estate owned	(37)	2,740
Deferred tax liability	6,227	2,356
Depreciation	1,527	1,471
Net losses on sale and transfer of other real estate owned	44	712
Net gains on sale of loans	(567)	(278)
Proceeds from sales of loans	23,672	25,140
Originations of loans held-for-sale	(23,105)	(24,836)
Net change in trading securities	(55)	(99,930)
Write-downs on venture capital investments	92	137
Gain on sales and calls of securities	(6,292)	(2,215)
Amortization/accretion of security premiums/discounts, net	1,114	1,314
Amortization of other intangible assets	1,428	1,491
Excess tax short-fall from share-based payment arrangements	69	565
Stock based compensation and stock issued to officers as compensation	1,037	546
Net change in accrued interest receivable and other assets	4,081	38,156
Net change in other liabilities	1,612	1,527
Net cash provided by/(used in) operating activities	39,845	(26,040)
Cash Flows from Investing Activities
Decrease in short-term investments	196,189	19,900
Increase in securities purchased under agreements to resell		(50,000)
Purchase of investment securities available-for-sale	(508,865)	(424,637)
Proceeds from sale of investment securities available-for-sale	320,234	148,134
Proceeds from repayments, maturities and calls of investment securities available-for-sale	57,495	226,173
Proceeds from repayments, maturities and calls of investment securities held-to-maturity	50,973	67,979
Redemptions of Federal Home Loan Bank stock	4,142	2,533
Net decrease in loans	61,833	131,822
Purchase of premises and equipment	(1,014)	(905)
Proceeds from sale of other real estate owned	1,351	10,186
Net increase in investment in affordable housing	(1,614)	(4,902)
Net cash provided by investing activities	180,724	126,283
Cash Flows from Financing Activities
Net increase in deposits	42,362	130,717
Net decrease in federal funds purchased and securities sold under agreements to repurchase	(100,000)
Advances from Federal Home Loan Bank	298,020	260,000
Repayment of Federal Home Loan Bank borrowings	(317,500)	(485,000)
Cash dividends paid	(3,828)	(4,012)
Redemption of series B preferred stock	(129,000)
Repayment of other borrowings		(879)
Proceeds from shares issued under Dividend Reinvestment Plan	62	67
Proceeds from exercise of stock options		647
Excess tax short-fall from share-based payment arrangements	(69)	(565)
Net cash used in financing activities	(209,953)	(99,025)
Increase in cash and cash equivalents	10,616	1,218
Cash and cash equivalents, beginning of the period	144,909	117,888
Cash and cash equivalents, end of the period	155,525	119,106
Cash paid during the period:
Interest	22,827	30,699
Income taxes paid/(refund)	8,562	(20,424)
Non-cash investing and financing activities:
Net change in unrealized holding gain on securities available-for-sale, net of tax	23,012	4,195
Transfers investment securities to available-for-sale from held-to-maturity	722,466
Transfers to other real estate owned from loans held for investment	366	8,338
Loans transferred from held for investment to held for sale, net		15,986
Loans to facilitate the sale of other real estate owned	$ 75