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Debt - Summary of Long-Term Debt (Detail) - USD ($) $ in Thousands	Jul. 31, 2019	Jun. 30, 2019	May 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt instrument carrying amount		$ 1,449,261		$ 1,577,127
Unamortized debt discount and debt issuance costs		(16,149)		(15,833)
Long-term debt and capital lease obligation		1,433,112		1,561,294
Less: current maturities of long-term debt		12,650		15,565
Long-term debt, net of current maturities		1,420,462		1,545,729
2023 Facility
Debt Instrument [Line Items]
Debt instrument carrying amount		73,000		179,000
2024 Notes
Debt Instrument [Line Items]
Debt instrument carrying amount		578,923		696,361
2024 Term Loan
Debt Instrument [Line Items]
Debt instrument carrying amount		157,075		458,250
2027 Notes
Debt Instrument [Line Items]
Debt instrument carrying amount	$ 75,000	400,000	$ 400,000
Other Finance Obligations
Debt Instrument [Line Items]
Debt instrument carrying amount		222,916		227,071
Finance Lease Obligations
Debt Instrument [Line Items]
Debt instrument carrying amount		$ 17,347		$ 16,445