GOODWILL AND OTHER INTANGIBLE ASSETS (Net Carrying Amount of Goodwill By Segment) (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill [Line Items]
Beginning balance	$ 347,149
WashingtonFirst, No Activity	0
Ending balance	347,149
Community Banking
Goodwill [Line Items]
Beginning balance	331,173
WashingtonFirst, No Activity	0
Ending balance	331,173
Insurance
Goodwill [Line Items]
Beginning balance	6,788
WashingtonFirst, No Activity	0
Ending balance	6,788
Investment Management
Goodwill [Line Items]
Beginning balance	9,188
WashingtonFirst, No Activity	0
Ending balance	$ 9,188

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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- Definition

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+ References

No definition available.

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