Supplemental Condensed Consolidating Guarantor and Non-Guarantor Financial Information Condensed Consolidating Statement Of Cash Flow (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Operating activities
Net cash (used in) provided by operating activities	$ 40,633	$ (30,731)
Investing activities
Payments for acquisition of businesses, net of cash received	(56)	(576)
Purchases of property and equipment	(11,983)	(17,533)
Other	96	64
Net cash used in investing activities	(11,943)	(18,045)
Financing activities
Payments of debt issue costs		(3,090)
Net issuance of common stock under equity compensation plans	9,353	8,662
Deposits	2,557	2,423
Purchase and retirement of common stock	(2,903)
Other	(154)	(326)
Net cash provided by financing activities	8,853	7,669
Effect of exchange rate changes on cash and cash equivalents	(4,638)	(2,585)
Net increase (decrease) in cash and cash equivalents	32,905	(43,692)
Cash and cash equivalents, beginning of period	149,760	283,680
Cash and cash equivalents, end of period	182,665	239,988
FTI Consulting, Inc.
Operating activities
Net cash (used in) provided by operating activities	(3,975)	(28,171)
Investing activities
Purchases of property and equipment	(1,533)	(6,000)
Other	96	25
Net cash used in investing activities	(1,437)	(5,975)
Financing activities
Payments of debt issue costs		(3,090)
Net issuance of common stock under equity compensation plans	9,353	8,662
Purchase and retirement of common stock	(2,903)
Other	418	(114)
Intercompany transfers	36,342	(10,315)
Net cash provided by financing activities	43,210	(4,857)
Net increase (decrease) in cash and cash equivalents	37,798
Cash and cash equivalents, beginning of period	35,211	171,090
Cash and cash equivalents, end of period	73,009	132,087
Guarantor Subsidiaries
Operating activities
Net cash (used in) provided by operating activities	42,564	8,296
Investing activities
Purchases of property and equipment	(7,821)	(8,887)
Net cash used in investing activities	(7,821)	(8,887)
Financing activities
Other	(572)	(212)
Intercompany transfers	(34,173)	803
Net cash provided by financing activities	(34,745)	591
Net increase (decrease) in cash and cash equivalents	(2)
Cash and cash equivalents, beginning of period	165	159
Cash and cash equivalents, end of period	163	159
Non-Guarantor Subsidiaries
Operating activities
Net cash (used in) provided by operating activities	2,044	(10,856)
Investing activities
Payments for acquisition of businesses, net of cash received	(56)	(576)
Purchases of property and equipment	(2,629)	(2,646)
Other		39
Net cash used in investing activities	(2,685)	(3,183)
Financing activities
Deposits	2,557	2,423
Intercompany transfers	(2,169)	9,512
Net cash provided by financing activities	388	11,935
Effect of exchange rate changes on cash and cash equivalents	(4,638)	(2,585)
Net increase (decrease) in cash and cash equivalents	(4,891)
Cash and cash equivalents, beginning of period	114,384	112,431
Cash and cash equivalents, end of period	$ 109,493	$ 107,742