Incentive Plans - Summary of Impact of LFI and Other Similar Deferred Compensation Arrangements (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share Based Compensation [Abstract]
Amortization, net of forfeitures	$ 51,770	$ 43,177	$ 81,793	$ 69,425
Change in the fair value of underlying investments	16,491	23,803	23,978	4,166
Total	$ 68,261	$ 66,980	$ 105,771	$ 73,591

Amount of expense recognized from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments), awarded to key employees or individuals. Excludes amount related to plans that cover generally all employees (for example, but not limited to, qualified pension plans).

No definition available.

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Balance Type:	debit
Period Type:	duration