XML 88 R75.htm IDEA: XBRL DOCUMENT v3.19.1

Fair Values of Assets and Liabilities - Losses Realized on Assets Measured on Non-Recurring Basis (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Impaired loans	$ (969)	$ (7,850)
Other real estate owned	(49)	(30)
Total losses	$ (1,018)	$ (7,880)

X

- Definition

Net losses on assets measured on nonrecurring basis.

+ References

No definition available.

+ Details

Name:	fcf_FairValueMeasurementOfAssetsOnNonrecurringBasisNetLoss
Namespace Prefix:	fcf_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Net losses on impaired loans still held at the end of the period.

+ References

No definition available.

+ Details

Name:	fcf_FairValueMeasurementOfAssetsOnNonrecurringBasisNetLossesOnImpairedLoans
Namespace Prefix:	fcf_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Net losses on other real estate owned still held at the end of the period

+ References

No definition available.

+ Details

Name:	fcf_FairValueMeasurementOfAssetsOnNonrecurringBasisNetLossesOnOtherRealEstateOwned
Namespace Prefix:	fcf_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	us-gaap_FairValueDisclosuresAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration