| **INCOME TAXES (Tables)**                              | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Income Tax Disclosure [Abstract]**                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Schedule of Components of Income Tax Expense (Benefit) | The provision/(benefit) for income taxes in the Consolidated Statement of Operations is comprised of the following components:  YEAR ENDED DECEMBER 31,  2013 2012 2011  (in thousands)Current:      Foreign $208 $107 $80Federal (79,281) 12,806 269,797State 5,099 12,145 141,056Total current (73,974) 25,058 410,933       Deferred:      Federal 189,274 (125,681) 453,456State 45,000 (5,825) 43,890Total deferred 234,274 (131,506) 497,346Total income tax provision/(benefit) $160,300 $(106,448) $908,279                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Schedule of Effective Income Tax Rate Reconciliation   | The following is a reconciliation of the U.S. federal statutory rate of 35.0% to the Company’s effective tax rate for each of the years indicated:  YEAR ENDED DECEMBER 31,  2013 2012 2011Federal income tax at statutory rate 35.0 % 35.0 % 35.0 %Increase/(decrease) in taxes resulting from:      Valuation allowance (0.1)% (2.5)% 0.3 %Tax-exempt income (4.1)% (5.3)% (1.0)%Bank owned life insurance (2.5)% (4.5)% (0.9)%State income taxes, net of federal tax benefit 4.8 % 3.5 % 5.2 %Investment tax credits(1) (2.1)% (19.8)% — %Low income housing credits (2.6)% (5.7)% (1.4)%Accelerated discount accretion — % — % 4.5 %Dividend from SCUSA  (7.1)% (31.2)% — %Other (1.0)% 7.1 % 0.3 %Effective tax rate 20.3 % (23.4)% 42.0 %(1) Investment tax credits in 2013 were the result of the Company's investment in a VIE. Investment tax credits in 2012 were the result of the Company's investment in direct financing lease transactions.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| Schedule of Deferred Tax Assets and Liabilities        | The tax effects of temporary differences that give rise to the deferred tax assets and deferred tax liabilities are presented below:  AT DECEMBER 31,  2013 2012  (in thousands)Deferred tax assets:    Allowance for loan losses $328,184 $380,503Unrealized loss on available-for-sale securities 129,170 —Unrealized loss on derivatives 22,085 46,333Net operating loss carry forwards 588,223 454,265Non-solicitation payments 14,837 24,024Employee benefits 70,345 66,380General business credit carry forwards 260,996 243,373Foreign tax credit carry forwards 60,688 60,688Broker commissions paid on originated mortgage loans 25,766 26,882Minimum tax credit carry forward 150,482 192,387IRC Section 382 recognized built in losses 25,818 31,578Recourse reserves 49,160 67,704Deferred interest expense 82,453 207,189Other 68,501 43,424Total gross deferred tax assets 1,876,708 1,844,730Valuation allowance (94,601) (95,201)Total deferred tax assets 1,782,107 1,749,529     Deferred tax liabilities:    Purchase accounting adjustments 8,976 15,911Deferred income 12,539 12,339Originated mortgage servicing rights 45,228 24,505Unrealized gain on available-for-sale portfolio — 105,349SCUSA Transaction deferred gain 471,762 368,716Leasing transactions 207,384 156,343Depreciation and amortization 285,158 258,697Other 3,102 27,246Total gross deferred tax liabilities 1,034,149 969,106     Net deferred tax asset $747,958 $780,423                                                                                                 |
| Schedule of Unrecognized Tax Benefits Roll Forward     | A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:  FederalState andLocal Tax AccruedInterestand Penalties UnrecognizedIncome TaxBenefits  (in thousands)Gross unrecognized tax benefits at January 1, 2011 $110,363 $26,588 $136,951SCUSA Transaction — (5,998) (5,998)Additions based on tax positions related to 2011 12,275 — 12,275Additions for tax positions of prior years 2,079 2,099 4,178Reductions for tax positions of prior years — (842) (842)Reductions to unrecognized tax benefits as a result of a lapse of the applicable statute of limitations (3,343) (441) (3,784)Settlements (13,691) (1,861) (15,552)Gross unrecognized tax benefits at December 31, 2011 107,683 19,545 127,228Additions based on tax positions related to 2012 2,536 — 2,536Additions for tax positions of prior years 21,000 5,280 26,280Reductions for tax positions of prior years (356) — (356)Reductions to unrecognized tax benefits as a result of a lapse of the applicable statute of limitations (750) (205) (955)Settlements (4,648) (1,597) (6,245)Gross unrecognized tax benefits at December 31, 2012 125,465 23,023 148,488Additions based on tax positions related to the current year 2,339 — 2,339Additions for tax positions of prior years — 936 936Gross unrecognized tax benefits at December 31, 2013 $127,804 $23,959 151,763Less: Federal, state and local income tax benefits     (14,324)Net unrecognized tax benefits that if recognized would impact the effective tax rate at December 31, 2013     $137,439 |

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| - Definition
Tabular disclosure of the components of income tax expense attributable to continuing operations for each year presented including, but not limited to: current tax expense (benefit), deferred tax expense (benefit), investment tax credits, government grants, the benefits of operating loss carryforwards, tax expense that results from allocating certain tax benefits either directly to contributed capital or to reduce goodwill or other noncurrent intangible assets of an acquired entity, adjustments of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity, and adjustments of the beginning-of-the-year balances of a valuation allowance because of a change in circumstances that causes a change in judgment about the realizability of the related deferred tax asset in future years.
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| - Definition
Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets.
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| - Definition
Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations.
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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32687-109319
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| - Definition
Tabular disclosure of the change in unrecognized tax benefits.
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