XML 88 R38.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Variable Interest Entities - Schedule of Maximum Potential Exposure (Detail) (USD $) In Thousands, unless otherwise specified | Mar. 31, 2014 | Dec. 31, 2013
--- | --- | ---
Variable Interest Entities [Abstract] |  |
Low Income Housing Limited Partnership Investments | $ 174 | $ 207

X
- Details
Name: | fcf_VariableInterestEntitiesAbstract
Namespace Prefix: | fcf_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph b -URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5728-111685 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=28200181&loc=d3e5747-111685 + Details
Name: | us-gaap_VariableInterestEntityEntityMaximumLossExposureAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant