| **ACCUMULATED OTHER COMPREHENSIVE INCOME / (LOSS) (Tables)**             | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
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| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
| Schedule of Accumulated Other Comprehensive Income (Loss)                | The following table presents the components of accumulated other comprehensive income/ (loss), net of related tax, for the three-month period endedMarch 31, 2015 and 2014, respectively.  Total OtherComprehensive Income/(Loss) Total AccumulatedOther Comprehensive Income/(Loss) Three-Month Period Ended March 31, 2015 December 31, 2014   March 31, 2015 PretaxActivity TaxEffect Net Activity BeginningBalance NetActivity EndingBalance (in thousands)Change in accumulated gains/(losses) on cash flow hedge derivative financial instruments$(29,009) $11,154 $(17,855)      Reclassification adjustment for net gains/(losses) on cash flow hedge derivative financial instruments (1)4,451 (1,711) 2,740      Net unrealized gains/(losses) on cash flow hedge derivative financial instruments(24,558) 9,443 (15,115) $(14,260) $(15,115) $(29,375)            Change in unrealized gains/(losses) on investment securities available-for-sale117,781 (45,964) 71,817      Reclassification adjustment for net gains/(losses) included in net income on non-OTTI securities (2)(9,557) 3,730 (5,827)      Net unrealized gains/(losses) on investment securities available-for-sale108,224 (42,234) 65,990 (52,515) 65,990 13,475            Pension and post-retirement actuarial gain/(loss)(3)1,018 (403) 615 (29,635) 615 (29,020)            As of March 31, 2015$84,684 $(33,194) $51,490 $(96,410) $51,490 $(44,920)(1) Net losses reclassified into Interest on borrowings and other debt obligations in the Condensed Consolidated Statement of Operations for settlements of interest rate swap contracts designated as cash flow hedges. (2) Net gains reclassified into Net gain on sale of investment securities sales in the Condensed Consolidated Statement of Operations for the sale of available-for-sale securities. (3) Included in the computation of net periodic pension costs. NOTE 13. ACCUMULATED OTHER COMPREHENSIVE INCOME / (LOSS) (continued) Total OtherComprehensive Income/(Loss) Total AccumulatedOther Comprehensive Income/(Loss) Three-Month Period Ended March 31, 2014 December 31, 2013   March 31, 2014 PretaxActivity TaxEffect Net Activity BeginningBalance NetActivity EndingBalance (in thousands)Change in accumulated gains/(losses) on cash flow hedge derivative financial instruments$(1,648) $586 $(1,062)      Reclassification adjustment for net losses on cash flow hedge derivative financial instruments13,685 (4,863) 8,822      Net unrealized gains/(losses) on cash flow hedge derivative financial instruments12,037 (4,277) 7,760 $(39,423) $7,760 $(31,663)            Change in unrealized gains/(losses) on investment securities available-for-sale2,566,682 (1,005,159) 1,561,523      Reclassification adjustment for net gains included in net income on non-OTTI securities(2)(2,430,483) 951,821 (1,478,662)      Net unrealized gains/(losses) on investment securities available-for-sale136,199 (53,338) 82,861 (199,392) 82,861 (116,531)            Pension and post-retirement actuarial gain/(loss)447 115 562 (15,553) 562 (14,991)            As of March 31, 2014$148,683 $(57,500) $91,183 $(254,368) $91,183 $(163,185)             |

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| - Definition
Tabular disclosure of the components of accumulated other comprehensive income (loss).
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580
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