Debt Agreements - Outstanding Debt Balances (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019	Jul. 16, 2019
Debt Instrument [Line Items]
Total face value	$ 1,210,982	$ 1,418,026	$ 625,000
Debt discount	(29,226)	(59,922)
Deferred financing fees	(4,934)	(5,263)
Total debt and Exchangeable Senior Notes	1,176,822	1,352,841
Long-term debt and Exchangeable Senior Notes, net	1,002,318	1,352,841
Term Loan Facility due 2026 [Member]
Debt Instrument [Line Items]
Total face value	418,026	418,026
Senior Notes due 2027 [Member]
Debt Instrument [Line Items]
Total face value	600,000	600,000
Exchangeable Senior Notes due 2022 [Member]
Debt Instrument [Line Items]
Total face value	192,956	$ 400,000
Exchangeable Notes
Debt Instrument [Line Items]
Less: Exchangeable Senior Notes—current	$ 174,504

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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