GOODWILL AND OTHER INTANGIBLE ASSETS GOODWILL AND OTHER INTANGIBLE ASSETS (Details 2) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Beginning balance	$ 469,433	$ 337,438
Addition from MetroCorp acquisition	0	131,995
Ending balance	469,433	469,433
Retail Banking
Goodwill [Line Items]
Beginning balance	357,207	320,566
Addition from MetroCorp acquisition	0	36,641
Ending balance	357,207	357,207
Commercial Banking
Goodwill [Line Items]
Beginning balance	112,226	16,872
Addition from MetroCorp acquisition	0	95,354
Ending balance	$ 112,226	$ 112,226

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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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.

+ References

No definition available.

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