Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash Flows from Operating Activities
Net income	$ 119,663	$ 102,252
Adjustments to reconcile net income to net cash provided by/(used in) operating activities:
Credit for loan losses	(8,400)	(8,800)
Provision for losses on other real estate owned	547	1,693
Deferred tax liability	14,327	13,846
Depreciation and amortization	22,330	5,911
Net gains on sale and transfer of other real estate owned	(2,006)	(3,467)
Net gains on sale of loans	(845)	(300)
Proceeds from sales of loans	28,507	15,791
Originations of loans held-for-sale	(26,689)	(15,491)
Income associated with debt redemption		(550)
Write-downs on venture capital investments	408	317
Write-downs on impaired securities	3,875	820
Net gains on sales and calls of securities	(506)	(7,647)
Amortization/accretion of security premiums/discounts, net	3,542	2,266
Loss on sales or disposal of fixed assets	138
Excess tax short-fall from share-based payment arrangements	5,602	1,177
Stock based compensation and stock issued to officers as compensation	3,923	2,948
Net change in accrued interest receivable and other assets	(30,929)	1,691
Net change in other liabilities	(9,432)	(8,377)
Net cash provided by operating activities	124,055	104,080
Cash Flows from Investing Activities
Decrease/(increase) in short-term investments	119,785	(75,873)
Purchase of investment securities available-for-sale	(1,323,149)	(892,706)
Proceeds from sale of investment securities available-for-sale	1,033,195	543,305
Proceeds from repayments, maturities and calls of investment securities available-for-sale	232,253	640,478
Purchase of Federal Home Loan Bank stock		(17,736)
Redemptions of Federal Home Loan Bank stock	13,535	8,646
Net increase in loans	(702,595)	(763,211)
Purchase of premises and equipment	(2,628)	(4,036)
Proceeds from sales of other real estate owned	10,524	28,543
Investment in affordable housing & alternative energy partnerships	(46,349)	(5,617)
Acquisition, net of cash acquired	6,572
Net cash used in investing activities	(658,857)	(538,207)
Cash Flows from Financing Activities
Net increase in deposits	1,034,442	713,362
Net decrease in federal funds purchased and securities sold under agreements to repurchase	(50,000)	(250,000)
Advances from Federal Home Loan Bank	4,842,000	8,252,400
Repayment of Federal Home Loan Bank borrowings	(5,192,000)	(8,218,600)
Cash dividends paid	(30,690)	(15,133)
Pruchase of treasury stock	(50,701)
Repurchase of trust preferred securities		(1,450)
Proceeds from shares issued under Dividend Reinvestment Plan	3,636	1,554
Proceeds from exercise of stock options	3,433
Taxes paid related to net share settlement of RSUs	(204)	(274)
Excess tax short-fall from share-based payment arrangements	(5,602)	(1,177)
Net cash provided by financing activities	554,314	480,682
Increase in cash and cash equivalents	19,512	46,555
Cash and cash equivalents, beginning of the period	176,830	153,747
Cash and cash equivalents, end of the period	196,342	200,302
Cash paid during the period:
Interest	52,614	59,478
Income taxes paid	67,776	52,864
Non-cash investing and financing activities:
Net change in unrealized holding gain on securities available-for-sale, net of tax	4,790	21,057
Net change in unrealized holding loss on cash flow hedge derivatives	(1,818)	(163)
Transfers of investment securities to available-for-sale from other assets	520
Transfers of trading securities to short-term investments		4,936
Transfers to other real estate owned from loans held for investment	3,914	$ 2,810
Issuance of stock related to acquisition	$ 82,857