| **PREMISES AND EQUIPMENT (As Restated) (Tables)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| **Property, Plant and Equipment [Abstract]**      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Summary of Premises and Equipment                 | Premises and equipment are carried at cost, less accumulated depreciation. Depreciation is calculated utilizing the straight-line method. Estimated useful lives are as follows:Office buildings 10 to 30 yearsLeasehold improvements(1) 10 to 30 yearsSoftware(2) 3 to 5 yearsFurniture, fixtures and equipment 3 to 10 yearsAutomobiles 5 years(1)  Leasehold improvements are depreciated over the shorter of the useful lives of the assets or the remaining term of the leases. The useful life of the leasehold improvements may be extended beyond the base term of the lease contract when the lease contract includes renewal option period(s) that are reasonably assured of being exercised at the date the leasehold improvements are purchased. At no point does the depreciable life exceed the economic useful life of the leasehold improvement or the expected term of the lease contract.(2)  Standard depreciable period for software is three years. However, for certain software implementation projects, a five-year period is utilized. A summary of premises and equipment, less accumulated depreciation, follows:  AT DECEMBER 31,  2015 2014  (in thousands)Land $46,835 $50,835Office buildings 193,313 206,601Furniture, fixtures, and equipment 324,717 258,351Leasehold improvements 457,266 413,218Computer software 763,578 563,139Automobiles and other 1,164 480Total premises and equipment 1,786,873 1,492,624Less accumulated depreciation (844,501) (637,953)Total premises and equipment, net $942,372 $854,671 |

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No definition available.
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| - Definition
Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph b -Article 5
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