Supplemental Condensed Consolidating Guarantor and Non-Guarantor Financial Information Condensed Consolidating Balance Sheet Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2014
Assets
Cash and cash equivalents	$ 182,665	$ 149,760	$ 239,988	$ 283,680
Accounts receivable, net	547,298	499,784
Other current assets	81,779	92,081
Total current assets	811,742	741,625
Property and equipment, net	68,764	74,760
Goodwill	1,189,602	1,198,298
Other intangible assets, net	57,568	63,935
Other assets	159,788	150,400
Total assets	2,287,464	2,229,018
Liabilities
Other current liabilities	325,042	347,077
Total current liabilities	325,042	347,077
Long-term debt, net	495,150	494,772
Other liabilities	264,029	239,566
Total liabilities	1,084,221	1,081,415
Stockholders' equity	1,203,243	1,147,603
Total liabilities and stockholders' equity	2,287,464	2,229,018
FTI Consulting, Inc.
Assets
Cash and cash equivalents	73,009	35,211	132,087	171,090
Accounts receivable, net	174,100	159,121
Other current assets	41,736	44,086
Total current assets	288,845	238,418
Property and equipment, net	30,270	33,699
Goodwill	558,978	558,978
Other intangible assets, net	23,891	25,863
Investments in subsidiaries	2,036,140	1,995,409
Other assets	52,437	40,359
Total assets	2,990,561	2,892,726
Liabilities
Intercompany payables	966,409	930,066
Other current liabilities	118,913	135,421
Total current liabilities	1,085,322	1,065,487
Long-term debt, net	495,150	494,772
Other liabilities	206,846	184,864
Total liabilities	1,787,318	1,745,123
Stockholders' equity	1,203,243	1,147,603
Total liabilities and stockholders' equity	2,990,561	2,892,726
Guarantor Subsidiaries
Assets
Cash and cash equivalents	163	165	159	159
Accounts receivable, net	176,861	169,488
Intercompany receivables	961,704	936,452
Other current assets	19,795	25,627
Total current assets	1,158,523	1,131,732
Property and equipment, net	13,773	13,409
Goodwill	416,053	416,053
Other intangible assets, net	14,473	15,571
Investments in subsidiaries	494,788	486,462
Other assets	69,685	72,981
Total assets	2,167,295	2,136,208
Liabilities
Intercompany payables		8,921
Other current liabilities	107,893	107,188
Total current liabilities	107,893	116,109
Other liabilities	14,233	12,562
Total liabilities	122,126	128,671
Stockholders' equity	2,045,169	2,007,537
Total liabilities and stockholders' equity	2,167,295	2,136,208
Non-Guarantor Subsidiaries
Assets
Cash and cash equivalents	109,493	114,384	$ 107,742	$ 112,431
Accounts receivable, net	196,337	171,175
Intercompany receivables	34,648	62,651
Other current assets	20,248	22,368
Total current assets	360,726	370,578
Property and equipment, net	24,721	27,652
Goodwill	214,571	223,267
Other intangible assets, net	38,610	43,542
Other assets	37,666	37,060
Total assets	676,294	702,099
Liabilities
Intercompany payables	29,943	60,116
Other current liabilities	98,236	104,468
Total current liabilities	128,179	164,584
Other liabilities	42,950	42,140
Total liabilities	171,129	206,724
Stockholders' equity	505,165	495,375
Total liabilities and stockholders' equity	676,294	702,099
Eliminations
Assets
Intercompany receivables	(996,352)	(999,103)
Total current assets	(996,352)	(999,103)
Other intangible assets, net	(19,406)	(21,041)
Investments in subsidiaries	(2,530,928)	(2,481,871)
Total assets	(3,546,686)	(3,502,015)
Liabilities
Intercompany payables	(996,352)	(999,103)
Total current liabilities	(996,352)	(999,103)
Total liabilities	(996,352)	(999,103)
Stockholders' equity	(2,550,334)	(2,502,912)
Total liabilities and stockholders' equity	$ (3,546,686)	$ (3,502,015)