Supplemental Condensed Consolidating Guarantor and Non-Guarantor Financial Information Condensed Consolidating Statement Of Cash Flow (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating activities
Net cash (used in) provided by operating activities	$ 135,401	$ 193,271	$ 120,188
Investing activities
Payments for acquisition of businesses, including contingent payments, net of cash received	(23,467)	(55,498)	(62,893)
Purchases of property and equipment	(39,256)	(42,544)	(27,759)
Other	5,128	(5,049)	246
Net cash used in investing activities	(57,595)	(103,091)	(90,406)
Financing activities
Payments of long-term debt and capital lease obligations	(6,014)	(6,021)	(377,859)
Deposits	13,071
Issuance of debt securities, net			292,608
Purchase and retirement of common stock	(4,367)	(66,763)	(50,032)
Net issuance of common stock under equity compensation plans	4,772	29,392	1,598
Other	(1,132)	263	(4,561)
Net cash provided by (used in) financing activities	6,330	(43,129)	(138,246)
Effects of exchange rate changes on cash and cash equivalents	(6,289)	1,997	826
Net (decrease) increase in cash and cash equivalents	77,847	49,048	(107,638)
Cash and cash equivalents, beginning of period	205,833	156,785	264,423
Cash and cash equivalents, end of period	283,680	205,833	156,785
FTI Consulting, Inc.
Operating activities
Net cash (used in) provided by operating activities	(36,921)	(37,166)	(63,218)
Investing activities
Payments for acquisition of businesses, including contingent payments, net of cash received	(14,729)	(12,555)	(41,722)
Purchases of property and equipment	(12,738)	(4,296)	(8,310)
Other	139	45	246
Net cash used in investing activities	(27,328)	(16,806)	(49,786)
Financing activities
Payments of long-term debt and capital lease obligations			(377,810)
Issuance of debt securities, net			292,608
Purchase and retirement of common stock	(4,367)	(66,763)	(50,032)
Net issuance of common stock under equity compensation plans	4,772	29,392	1,598
Other	366	1,515	(2,441)
Intercompany transfers	122,625	135,108	154,564
Net cash provided by (used in) financing activities	123,396	99,252	18,487
Net (decrease) increase in cash and cash equivalents	59,147	45,280	(94,517)
Cash and cash equivalents, beginning of period	111,943	66,663	161,180
Cash and cash equivalents, end of period	171,090	111,943	66,663
Guarantor Subsidiaries
Operating activities
Net cash (used in) provided by operating activities	142,540	178,234	172,578
Investing activities
Payments for acquisition of businesses, including contingent payments, net of cash received	(7,783)	(7,157)
Purchases of property and equipment	(13,080)	(17,507)	(15,689)
Net cash used in investing activities	(20,863)	(24,664)	(15,689)
Financing activities
Payments of long-term debt and capital lease obligations	(6,000)	(6,000)	(49)
Other	(555)
Intercompany transfers	(115,457)	(147,686)	(156,427)
Net cash provided by (used in) financing activities	(122,012)	(153,686)	(156,476)
Net (decrease) increase in cash and cash equivalents	(335)	(116)	413
Cash and cash equivalents, beginning of period	494	610	197
Cash and cash equivalents, end of period	159	494	610
Non-Guarantor Subsidiaries
Operating activities
Net cash (used in) provided by operating activities	29,782	52,203	10,828
Investing activities
Payments for acquisition of businesses, including contingent payments, net of cash received	(955)	(35,786)	(21,171)
Purchases of property and equipment	(13,438)	(20,741)	(3,760)
Other	4,989	(5,094)
Net cash used in investing activities	(9,404)	(61,621)	(24,931)
Financing activities
Payments of long-term debt and capital lease obligations	(14)	(21)
Deposits	13,071
Other	(943)	(1,252)	(2,120)
Intercompany transfers	(7,168)	12,578	1,863
Net cash provided by (used in) financing activities	4,946	11,305	(257)
Effects of exchange rate changes on cash and cash equivalents	(6,289)	1,997	826
Net (decrease) increase in cash and cash equivalents	19,035	3,884	(13,534)
Cash and cash equivalents, beginning of period	93,396	89,512	103,046
Cash and cash equivalents, end of period	$ 112,431	$ 93,396	$ 89,512

Intercompany transfers among subsidiaries that are eliminated in consolidation.

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The net cash associated with the amount received from holders to acquire the entity's shares under incentive and share awards, including stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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The net cash outflow or inflow from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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The cash outflow to reacquire common stock during the period.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership.

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The cash inflow associated with security instrument that either represents a creditor or an ownership relationship with the holder of the investment security with a maturity of beyond one year or normal operating cycle, if longer. Includes proceeds from (a) debt, (b) capital lease obligations, (c) mandatory redeemable capital securities, and (d) any combination of (a), (b), or (c).

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The net cash inflow or outflow from other financing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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The cash outflow associated with security instruments that either represent a creditor or an ownership relationship with the holder of the investment security with a maturity of beyond one year or normal operating cycle, if longer. Includes repayments of (a) debt, (b) capital lease obligations, (c) mandatory redeemable capital securities, and (d) any combination of (a), (b), or (c).

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