Prepetition Revolving Credit Facility, Senior Notes and Exit Debt - Summary of Carrying Value of Long-term Debt, Net of Unamortized Discount, Premium and Debt Issuance Costs (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Apr. 23, 2021
Debt Instrument [Line Items]
Total Exit Debt, net	$ 306,145	$ 285,982
Exit Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Total Exit Debt, net	123,478
Exit Term Loans [Member]
Debt Instrument [Line Items]
Total Exit Debt, net	98,995
Exit Notes [Member]
Debt Instrument [Line Items]
Total Exit Debt, net	$ 83,672