| **ACCUMULATED OTHER COMPREHENSIVE INCOME / (LOSS) (Tables)**             | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           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| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     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| 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 and six-month periods endedJune 30, 2016, and 2015, respectively.Total OtherComprehensive Income/(Loss)Total AccumulatedOther Comprehensive (Loss)/IncomeThree-Month Period Ended June 30, 2016March 31, 2016June 30, 2016PretaxActivityTaxEffectNet ActivityBeginningBalanceNetActivityEndingBalance(in thousands)Change in accumulated (losses)/gains on cash flow hedge derivative financial instruments$(16,806)$627$(16,179)   Reclassification adjustment for net gains/(losses) on cash flow hedge derivative financial instruments (1)1,462(55)1,407   Net unrealized (losses)/gains on cash flow hedge derivative financial instruments(15,344)572(14,772)$(49,109)$(14,772)$(63,881)Change in unrealized gains/(losses) on investment securities available-for-sale84,909(33,295)51,614   Reclassification adjustment for net (gains)/losses included in net income/(expense) on non-OTTI securities (2)(31,339)12,289(19,050)Reclassification adjustment for net losses/(gains) included in net income/(expense) on OTTI securities (3)34(13)21Reclassification adjustment for net (gains)/losses included in net income(31,305)12,276(19,029)   Net unrealized gains/(losses) on investment securities available-for-sale53,604(21,019)32,58548,89832,58581,483Pension and post-retirement actuarial gain/(loss) (4)929(364)565(26,468)565(25,903)As of June 30, 2016$39,189$(20,811)$18,378$(26,679)$18,378$(8,301)            (1)  Net gains 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 in Note 11 to the Condensed Consolidated Financial Statements. (2)  Net gains reclassified into Net gain on sale of investment securities in the Condensed Consolidated Statement of Operations for the sale of available-for-sale securities. (3)  Unrealized losses previously recognized in accumulated other comprehensive income on securities for which OTTI was recognized during the period. See further discussion in Note 3 to the Condensed Consolidated Financial Statements.(4)  Included in the computation of net periodic pension costs. NOTE 13. ACCUMULATED OTHER COMPREHENSIVE INCOME / (LOSS) (continued) Total OtherComprehensive Income/(Loss) Total AccumulatedOther Comprehensive (Loss)/Income For the Six-Month Period Ended June 30, 2016 December 31, 2015  June 30, 2016 PretaxActivity TaxEffect Net Activity BeginningBalance NetActivity EndingBalance (in thousands)Change in accumulated (losses)/gains on cash flow hedge derivative financial instruments$(81,001) $31,164 $(49,837)      Reclassification adjustment for net gains/(losses) on cash flow hedge derivative financial instruments (1)4,125 (1,587) 2,538      Net unrealized (losses)/gains on cash flow hedge derivative financial instruments(76,876) 29,577 (47,299) $(16,582) $(47,299) $(63,881)            Change in unrealized gains/(losses) on investment securities available-for-sale350,084 (137,526) 212,558      Reclassification adjustment for net (gains)/losses included in net income/(expense) on non-OTTI securities (2)(57,770) 22,694 (35,076)      Reclassification adjustment for net losses/(gains) included in net income/(expense) on OTTI securities (3)44 (17) 27      Reclassification adjustment for net (gains)/losses included in net income(57,726) 22,677 (35,049)      Net unrealized gains/(losses) on investment securities available-for-sale292,358 (114,849) 177,509 (96,026) 177,509 81,483            Pension and post-retirement actuarial gains/(losses)(4)1,858 (728) 1,130 (27,033) 1,130 (25,903)            As of June 30, 2016$217,340$(86,000)$131,340$(139,641)$131,340$(8,301)            (1)  Net gains 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 in Note 11 to the Condensed Consolidated Financial Statements. (2)  Net gains reclassified into Net gain on sale of investment securities in the Condensed Consolidated Statement of Operations for the sale of available-for-sale securities. (3)  Unrealized losses previously recognized in accumulated other comprehensive income on securities for which OTTI was recognized during the period. See further discussion in Note 3 to the Condensed Consolidated Financial Statements.(4)  Included in the computation of net periodic pension costs. NOTE 13. ACCUMULATED OTHER COMPREHENSIVE INCOME / (LOSS) (continued) Total OtherComprehensive Income/(Loss) Total AccumulatedOther Comprehensive (Loss)/Income Three-Month Period Ended June 30, 2015 March 31, 2015   June 30, 2015 PretaxActivity TaxEffect Net Activity BeginningBalance NetActivity EndingBalance (in thousands)Change in accumulated gains/(losses) on cash flow hedge derivative financial instruments$7,763 $(2,891) $4,872      Reclassification adjustment for net gains/(losses) on cash flow hedge derivative financial instruments (1)3,732 (1,390) 2,342      Net unrealized gains/(losses) on cash flow hedge derivative financial instruments11,495 (4,281) 7,214 $(29,375) $7,214 $(22,161)            Change in unrealized (losses)/gains on investment securities available-for-sale(133,445) 51,195 (82,250)      Reclassification adjustment for net (gains)/losses included in net income/(expense) on non-OTTI securities (2)(10,799) 4,143 (6,656)      Reclassification adjustment for net losses/(gains) included in net income/(expense) on OTTI securities (3)1,092 (419) 673      Reclassification adjustment for net (gains)/losses included in net income(9,707) 3,724 (5,983)      Net unrealized (losses)/gains on investment securities available-for-sale(143,152) 54,919 (88,233) 13,475 (88,233) (74,758)            Pension and post-retirement actuarial gains/(losses)(3)1,018 (581) 437 (29,020) 437 (28,583)            As of June 30, 2015$(130,639) $50,057 $(80,582) $(44,920) $(80,582) $(125,502)            (1)  Net gains reclassified into Interest on borrowings and other debt obligations in the Condensed Consolidated Statement of Operations for settlements of interest rate swap contracts designated as cash flow hedges in Note 11.(2)  Net gains reclassified into Net gains on sale of investment securities sales in the Condensed Consolidated Statement of Operations for the sale of available-for-sale securities.(3)  Included in the computation of net periodic pension costs.NOTE 13. ACCUMULATED OTHER COMPREHENSIVE INCOME / (LOSS) (continued)             Total OtherComprehensive Income/(Loss) Total AccumulatedOther Comprehensive (Loss)/Income For the Six-Month Period Ended Jun 30, 2015 December 31, 2014   June 30, 2015 PretaxActivity TaxEffect Net Activity BeginningBalance NetActivity EndingBalance (in thousands)Change in accumulated (losses)/gains on cash flow hedge derivative financial instruments$(21,246) $8,395 $(12,851)      Reclassification adjustment for net gains/(losses) on cash flow hedge derivative financial instruments(1)8,183 (3,233) 4,950      Net unrealized (losses)/gains on cash flow hedge derivative financial instruments(13,063) 5,162 (7,901) $(14,260) $(7,901) $(22,161)            Change in unrealized (losses)/gains on investment securities available-for-sale(15,664) 5,689 (9,975)      Reclassification adjustment for net(losses)/gains included in net income/(expense) on non-OTTI securities (2)(20,356) 7,393 (12,963)      Reclassification adjustment for net losses/(gains) included in net income/(expense) on OTTI securities (3)1,092 (397) 695      Reclassification adjustment for net (losses)/gains included in net income(19,264) 6,996 (12,268)      Net unrealized (losses)/gains on investment securities available-for-sale(34,928) 12,685 (22,243) (52,515) (22,243) (74,758)            Pension and post-retirement actuarial gains/(losses)(3)2,036 (984) 1,052 (29,635) 1,052 (28,583)            As of June 30, 2015$(45,955) $16,863 $(29,092) $(96,410) $(29,092) $(125,502)(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 |

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| - References
No definition available.
+ Details**Name:**us-gaap_AccumulatedOtherComprehensiveIncomeLossNetOfTaxAbstract**Namespace Prefix:**us-gaap_**Data Type:**xbrli:stringItemType**Balance Type:**na**Period Type:**duration |
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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=66004124&loc=SL7669686-108580
+ Details**Name:**us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock**Namespace Prefix:**us-gaap_**Data Type:**nonnum:textBlockItemType**Balance Type:**na**Period Type:**duration |