Commitments and Contingencies - Summary of Future Minimum Lease Payments for Capital and Operating Lease (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Schedule Of Operating And Capital Leased Assets [Line Items]
Present value of payments, 2015	$ 1,090
Present value of payments, 2016	429
Present value of payments, 2017	129
Present value of payments, 2018	4
Present value of payments, 2019	0
Present value of payments, Thereafter	0
Present value of payments, Total	1,652
Interest, 2015	51
Interest, 2016	41
Interest, 2017	13
Interest, 2018	2
Interest, 2019	0
Interest, Thereafter	0
Interest, Total	107
Capital lease payments, 2015	1,141
Capital lease payments, 2016	470
Capital lease payments, 2017	142
Capital lease payments, 2018	6
Capital lease payments, 2019	0
Capital lease payments, Thereafter	0
Capital Lease Payments, Total	1,759
Operating leases, 2015	6,348
Operating leases, 2016	5,498
Operating leases, 2017	3,601
Operating leases, 2018	1,634
Operating leases, 2019	716
Operating leases, Thereafter	339
Operating leases, Total	18,136
Total leases, 2015	7,489
Total leases, 2016	5,968
Total leases, 2017	3,743
Total leases, 2018	1,640
Total leases, 2019	716
Total leases, Thereafter	339
Total leases, Total	19,895kfrc_LeasesFutureMinimumPaymentsDue
Furniture and Equipment [Member]
Schedule Of Operating And Capital Leased Assets [Line Items]
Operating leases, 2015	112
Operating leases, 2016	34
Operating leases, 2017	0
Operating leases, 2018	0
Operating leases, 2019	0
Operating leases, Thereafter	0
Operating leases, Total	146
Facilities [Member]
Schedule Of Operating And Capital Leased Assets [Line Items]
Operating leases, 2015	6,236
Operating leases, 2016	5,464
Operating leases, 2017	3,601
Operating leases, 2018	1,634
Operating leases, 2019	716
Operating leases, Thereafter	339
Operating leases, Total	$ 17,990

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Amount of minimum lease payments for capital leases.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

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Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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