Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Deferred Tax Assets:
Basis adjustments	$ 233,371	$ 288,764
Compensation and benefits	167,631	159,799
Net operating loss and tax credit carryforwards	272,456	249,509
Depreciation and amortization	1,815	1,764
Other	62,159	35,801
Gross deferred tax assets	737,432	735,637
Valuation allowance	(76,486)	(73,114)	$ (61,456)	$ (69,593)
Deferred tax assets (net of valuation allowance)	660,946	662,523
Deferred Tax Liabilities:
Depreciation and amortization	12,019	14,550
Compensation and benefits	7,058	9,816
Goodwill	29,876	26,124
Other	28,754	19,828
Deferred tax liabilities	77,707	70,318
Net deferred tax assets	$ 583,239	$ 592,205