Supplemental Condensed Consolidating Guarantor and Non-Guarantor Financial Information Condensed Consolidating Balance Sheet Information (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Assets
Cash and cash equivalents	$ 114,451	$ 149,760	$ 225,295	$ 283,680
Accounts receivable, net	553,230	499,784
Other current assets	76,670	92,081
Total current assets	744,351	741,625
Property and equipment, net	71,263	74,760
Goodwill	1,198,070	1,198,298
Other intangible assets, net	61,193	63,935
Other assets	150,167	150,400
Total assets	2,225,044	2,229,018
Liabilities
Other current liabilities	287,519	347,077
Total current liabilities	287,519	347,077
Long-term debt, net	501,961	494,772
Other liabilities	254,318	239,566
Total liabilities	1,043,798	1,081,415
Stockholders' equity	1,181,246	1,147,603
Total liabilities and stockholders' equity	2,225,044	2,229,018
FTI Consulting, Inc.
Assets
Cash and cash equivalents	13,992	35,211	135,170	171,090
Accounts receivable, net	176,302	159,121
Other current assets	33,076	44,086
Total current assets	223,370	238,418
Property and equipment, net	31,765	33,699
Goodwill	558,978	558,978
Other intangible assets, net	24,877	25,863
Investments in subsidiaries	2,021,892	1,995,409
Other assets	40,855	40,359
Total assets	2,901,737	2,892,726
Liabilities
Intercompany payables	914,711	930,066
Other current liabilities	109,576	135,421
Total current liabilities	1,024,287	1,065,487
Long-term debt, net	501,961	494,772
Other liabilities	194,243	184,864
Total liabilities	1,720,491	1,745,123
Stockholders' equity	1,181,246	1,147,603
Total liabilities and stockholders' equity	2,901,737	2,892,726
Guarantor Subsidiaries
Assets
Cash and cash equivalents	163	165	156	159
Accounts receivable, net	191,471	169,488
Intercompany receivables	921,720	936,452
Other current assets	22,789	25,627
Total current assets	1,136,143	1,131,732
Property and equipment, net	12,649	13,409
Goodwill	416,053	416,053
Other intangible assets, net	15,013	15,571
Investments in subsidiaries	495,463	486,462
Other assets	70,630	72,981
Total assets	2,145,951	2,136,208
Liabilities
Intercompany payables	7,087	8,921
Other current liabilities	92,243	107,188
Total current liabilities	99,330	116,109
Other liabilities	14,387	12,562
Total liabilities	113,717	128,671
Stockholders' equity	2,032,234	2,007,537
Total liabilities and stockholders' equity	2,145,951	2,136,208
Non-Guarantor Subsidiaries
Assets
Cash and cash equivalents	100,296	114,384	$ 89,969	$ 112,431
Accounts receivable, net	185,457	171,175
Intercompany receivables	39,450	62,651
Other current assets	20,805	22,368
Total current assets	346,008	370,578
Property and equipment, net	26,849	27,652
Goodwill	223,039	223,267
Other intangible assets, net	41,528	43,542
Other assets	38,682	37,060
Total assets	676,106	702,099
Liabilities
Intercompany payables	39,372	60,116
Other current liabilities	85,700	104,468
Total current liabilities	125,072	164,584
Other liabilities	45,688	42,140
Total liabilities	170,760	206,724
Stockholders' equity	505,346	495,375
Total liabilities and stockholders' equity	676,106	702,099
Eliminations
Assets
Intercompany receivables	(961,170)	(999,103)
Total current assets	(961,170)	(999,103)
Other intangible assets, net	(20,225)	(21,041)
Investments in subsidiaries	(2,517,355)	(2,481,871)
Total assets	(3,498,750)	(3,502,015)
Liabilities
Intercompany payables	(961,170)	(999,103)
Total current liabilities	(961,170)	(999,103)
Total liabilities	(961,170)	(999,103)
Stockholders' equity	(2,537,580)	(2,502,912)
Total liabilities and stockholders' equity	$ (3,498,750)	$ (3,502,015)