Stock-Based Compensation - Short-Term Incentive Plan - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2019 USD ($)
2019 STIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance component, percentage of weighted revenue	20.00%
Performance component, percentage of weighted adjusted EBITDA	80.00%
2019 STIP | Certain Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of incentive awards in shares	50.00%
Percentage of incentive awards in cash	50.00%
2019 STIP | All Other Participants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of incentive awards in cash	100.00%
2018 STIP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Short term incentive award settled	$ 0