Business Segments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Total interest income	$ 90,584	$ 107,247	$ 269,798	$ 313,661
Interest expense	(13,657)	(17,424)	(44,584)	(51,911)
Net interest income	76,927	89,823	225,214	261,750
Provision for Loan and Lease Losses, net	(23,469)	(51,579)	(51,703)	(109,311)
Total non-interest income (loss), net	20,215	35,977	48,873	38,202
Non-interest expenses	(54,926)	(69,090)	(163,608)	(189,859)
Intersegment revenues	0	0	0	0
Intersegment expenses	0	0	0	0
Income (loss) before Income Taxes, Parent	18,747	5,131	58,776	782
Total assets	6,592,113		6,592,113		$ 7,099,149
Banking [Member]
Segment Reporting Information [Line Items]
Total interest income	82,564	97,264	243,389	285,251
Interest expense	(6,733)	(7,036)	(20,840)	(21,600)
Net interest income	75,831	90,228	222,549	263,651
Provision for Loan and Lease Losses, net	(23,469)	(51,579)	(51,703)	(109,311)
Total non-interest income (loss), net	8,918	30,098	24,927	16,136
Non-interest expenses	(50,095)	(63,106)	(147,881)	(169,264)
Intersegment revenues	375	351	1,162	1,058
Intersegment expenses	(86)	(69)	(235)	(228)
Income (loss) before Income Taxes, Parent	11,474	5,923	48,819	2,042
Total assets	5,715,958	5,990,125	5,715,958	5,990,125
Financial Services
Segment Reporting Information [Line Items]
Total interest income	15	25	49	71
Interest expense	0	0	0	0
Net interest income	15	25	49	71
Provision for Loan and Lease Losses, net	0	0	0	0
Total non-interest income (loss), net	6,379	6,513	19,309	20,416
Non-interest expenses	(3,757)	(5,063)	(11,610)	(16,586)
Intersegment revenues	0	0	0	0
Intersegment expenses	(272)	(252)	(849)	(770)
Income (loss) before Income Taxes, Parent	2,365	1,223	6,899	3,131
Total assets	19,433	20,594	19,433	20,594
Treasury [Member]
Segment Reporting Information [Line Items]
Total interest income	8,005	9,958	26,360	28,339
Interest expense	(6,924)	(10,388)	(23,744)	(30,311)
Net interest income	1,081	(430)	2,616	(1,972)
Provision for Loan and Lease Losses, net	0	0	0	0
Total non-interest income (loss), net	4,918	(634)	4,637	1,650
Non-interest expenses	(1,074)	(921)	(4,117)	(4,009)
Intersegment revenues	86	69	235	228
Intersegment expenses	(103)	(99)	(313)	(288)
Income (loss) before Income Taxes, Parent	4,908	(2,015)	3,058	(4,391)
Total assets	1,801,752	2,117,569	1,801,752	2,117,569
Major Segment [Member]
Segment Reporting Information [Line Items]
Total interest income	90,584	107,247	269,798	313,661
Interest expense	(13,657)	(17,424)	(44,584)	(51,911)
Net interest income	76,927	89,823	225,214	261,750
Provision for Loan and Lease Losses, net	(23,469)	(51,579)	(51,703)	(109,311)
Total non-interest income (loss), net	20,215	35,977	48,873	38,202
Non-interest expenses	(54,926)	(69,090)	(163,608)	(189,859)
Intersegment revenues	461	420	1,397	1,286
Intersegment expenses	(461)	(420)	(1,397)	(1,286)
Income (loss) before Income Taxes, Parent	18,747	5,131	58,776	782
Total assets	7,537,143	8,128,288	7,537,143	8,128,288
Intersegment Elimination [Member]
Segment Reporting Information [Line Items]
Total interest income	0	0	0	0
Interest expense	0	0	0	0
Net interest income	0	0	0	0
Provision for Loan and Lease Losses, net	0	0	0	0
Total non-interest income (loss), net	0	0	0	0
Non-interest expenses	0	0	0	0
Intersegment revenues	(461)	(420)	(1,397)	(1,286)
Intersegment expenses	461	420	1,397	1,286
Income (loss) before Income Taxes, Parent	0	0	0	0
Total assets	(945,031)	(924,466)	(945,031)	(924,466)
Consolidated Total [Member]
Segment Reporting Information [Line Items]
Total interest income	90,584	107,247	269,798	313,661
Interest expense	(13,657)	(17,424)	(44,584)	(51,911)
Net interest income	76,927	89,823	225,214	261,750
Provision for Loan and Lease Losses, net	(23,469)	(51,579)	(51,703)	(109,311)
Total non-interest income (loss), net	20,215	35,977	48,873	38,202
Non-interest expenses	(54,926)	(69,090)	(163,608)	(189,859)
Intersegment revenues	0	0	0	0
Intersegment expenses	0	0	0	0
Income (loss) before Income Taxes, Parent	18,747	5,131	58,776	782
Total assets	$ 6,592,112	$ 7,203,822	$ 6,592,112	$ 7,203,822

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Costs of sales and operating expenses for the period incurred from transactions with related parties.

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Represents the total of interest and dividend income, including any amortization and accretion (as applicable) of discounts and premiums, earned from (1) loans and leases whether held-for-sale or held-in-portfolio; (2) investment securities; (3) federal funds sold; (4) securities purchased under agreements to resell; (5) investments in banker's acceptances, commercial paper, or certificates of deposit; (6) dividend income; or (7) other investments not otherwise specified herein.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The net amount of operating interest income (expense).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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