Stock-based Compensation - Summary of Measured Based on an Average of Our stock Price (Detail)	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company Stock Price Hurdle | $ / shares	$ 165.00
Number of RSUs Eligible to Vest | shares	750,000
Performance Period Commencement	2 years
Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company Stock Price Hurdle | $ / shares	$ 200.00
Number of RSUs Eligible to Vest | shares	750,000
Performance Period Commencement	3 years
Tranche Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company Stock Price Hurdle | $ / shares	$ 235.00
Number of RSUs Eligible to Vest | shares	2,000,000
Performance Period Commencement	4 years
Tranche Four [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company Stock Price Hurdle | $ / shares	$ 270.00
Number of RSUs Eligible to Vest | shares	2,000,000
Performance Period Commencement	5 years
Tranche Five [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company Stock Price Hurdle | $ / shares	$ 305.00
Number of RSUs Eligible to Vest | shares	2,000,000
Performance Period Commencement	5 years
Tranche Six [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company Stock Price Hurdle | $ / shares	$ 340.00
Number of RSUs Eligible to Vest | shares	2,000,000
Performance Period Commencement	5 years
Tranche Seven [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company Stock Price Hurdle | $ / shares	$ 375.00
Number of RSUs Eligible to Vest | shares	2,000,000
Performance Period Commencement	5 years