XML 92 R65.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Investment Securities - Additional Information (Detail) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2013 Securities | Dec. 31, 2012 Securities
Schedule of Available-for-sale Securities [Line Items] |  |
Number of securities in an unrealized loss position | 219 | 57
Percentage of combined depreciation of the combined reported value of the aggregate securities portfolio | 5.06% | 2.78%
Carrying value of securities pledged | $ 284,770,000 | $ 292,880,000
OTTI charges incurred | $ 320,000 | $ 942,000
Reduced severity rate | 10.00% |
Severity rate reduction period | 3 years |
Continuous Loss Position More Than Twelve Months |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Number of securities in an unrealized loss position | 32 |
Mortgage-backed securities Non-Agency Alt-A residential |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Voluntary constant prepayment rate | 2.00% |
Constant default rate scenario | 16.00% |
Severity rate | 55.00% |

X
- Definition Carrying value of securities pledged. + References No definition available. + Details
Name: | fcbc_CarryingValueOfSecuritiesPledged
Namespace Prefix: | fcbc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Constant default rate scenario. + References No definition available. + Details
Name: | fcbc_ConstantDefaultRateScenario
Namespace Prefix: | fcbc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of securities in an unrealized loss position. + References No definition available. + Details
Name: | fcbc_NumberOfSecuritiesInUnrealizedLossPosition
Namespace Prefix: | fcbc_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Other than temporary impairment charges incurred. + References No definition available. + Details
Name: | fcbc_OtherThanTemporaryImpairmentChargesIncurred
Namespace Prefix: | fcbc_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage of combined depreciation of the combined reported value of the aggregate securities portfolio. + References No definition available. + Details
Name: | fcbc_PercentageOfCombinedDepreciationOfCombinedReportedValueOfAggregateSecuritiesPortfolio
Namespace Prefix: | fcbc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Reduced severity rate. + References No definition available. + Details
Name: | fcbc_ReducedSeverityRate
Namespace Prefix: | fcbc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Severity rate. + References No definition available. + Details
Name: | fcbc_SeverityRate
Namespace Prefix: | fcbc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Severity rate reduction period. + References No definition available. + Details
Name: | fcbc_SeverityRateReductionPeriod
Namespace Prefix: | fcbc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Definition Voluntary constant prepayment rate. + References No definition available. + Details
Name: | fcbc_VoluntaryConstantPrepaymentRate
Namespace Prefix: | fcbc_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration