Segment Information - Components of Segment Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Components of Segment Information
Operating income (loss)	$ 52,839	$ (28,852)	$ 63,706
Revenue from Contract with Customer, Including Assessed Tax	905,640	844,127	876,757
Revenues	926,958	871,014	965,474
Reimbursable expenses	(21,318)	(26,887)	(88,717)
Gain (Loss) Related To Litigation Settlement And Other Operating Gains	(198)	150	1,196
Depreciation and amortization expense	21,686	24,277	28,365
Goodwill, Impairment Loss	0	59,816	0
Other expense, net	(27,197)	5,021	11,215
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest, Total	80,036	(33,873)	52,491
Business Advisory [Member]
Components of Segment Information
Revenue from Contract with Customer, Including Assessed Tax	291,663	267,361	252,508
Goodwill, Impairment Loss		(59,816)
Education [Member]
Components of Segment Information
Revenue from Contract with Customer, Including Assessed Tax	236,400	223,329	225,028
Healthcare
Components of Segment Information
Revenue from Contract with Customer, Including Assessed Tax	377,577	353,437	399,221
Operating Segments [Member]
Components of Segment Information
Operating income (loss)	205,018	190,474	231,160
Operating Segments [Member] | Business Advisory [Member]
Components of Segment Information
Operating income (loss)	$ 48,236	$ 48,046	$ 49,695
Segment operating income as a percentage of segment revenues	16.50%	18.00%	19.70%
Revenue from Contract with Customer, Including Assessed Tax	$ 291,663	$ 267,361	$ 252,508
Operating Segments [Member] | Education [Member]
Components of Segment Information
Operating income (loss)	$ 52,772	$ 47,503	$ 55,741
Segment operating income as a percentage of segment revenues	22.30%	21.30%	24.80%
Revenue from Contract with Customer, Including Assessed Tax	$ 236,400	$ 223,329	$ 225,028
Operating Segments [Member] | Healthcare
Components of Segment Information
Operating income (loss)	$ 104,010	$ 94,925	$ 125,724
Segment operating income as a percentage of segment revenues	27.50%	26.90%	31.50%
Revenue from Contract with Customer, Including Assessed Tax	$ 377,577	$ 353,437	$ 399,221
Segment Reconciling Items [Member]
Components of Segment Information
Other operating expenses and gains	131,372	135,255	140,285
Gain (Loss) Related To Litigation Settlement And Other Operating Gains	173	(150)	(1,196)
Depreciation and amortization expense	20,634	24,405	28,365
Goodwill, Impairment Loss	0	59,816	0
Other expense, net	$ (27,197)	$ 5,021	$ 11,215