Financial Instruments and Fair Value Measurements - Carrying Value and Estimated Fair Values for Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial liabilities
Interest rate swap		$ 4,059
Carrying Amount
Financial assets
Interest rate swap	$ 0	1,683
Financial liabilities
Interest rate swap	14,452	4,059
Carrying Amount | Credit Facility | 2023 Term A
Financial liabilities
Senior secured term loan	207,261	217,791
Carrying Amount | Credit Facility | 2024 Term B
Financial liabilities
Senior secured term loan	317,936	320,515
Fair Value
Financial assets
Interest rate swap	0	1,683
Financial liabilities
Interest rate swap	14,452	4,059
Fair Value | Credit Facility | 2023 Term A
Financial liabilities
Senior secured term loan	206,388	218,625
Fair Value | Credit Facility | 2024 Term B
Financial liabilities
Senior secured term loan	$ 324,163	$ 319,517