Recent Pronouncements (Details)	6 Months Ended
Jun. 30, 2012
Recent Pronouncements (Textual) [Abstract]
Percentage of goodwill impairment test required under existing guidance threshold likelihood	0.50

Percentage of goodwill impairment test required under existing guidance threshold likelihood.

No definition available.

Name:	icfi_PercentageOfGoodwillImpairmentTestRequiredUnderExistingGuidanceThresholdLikelihood
Namespace Prefix:	icfi_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration