Aggregate Scheduled Maturities of Debt Outstanding (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
2019	$ 63,446
2020	56,650
2021	496,696
2022	810,526
2023	1,707,476
Later	885,028
Total debt before unamortized financing costs	4,019,822	$ 4,059,238
Less-Unamortized financing costs	(21,189)	(19,229)
Total debt after unamortized financing costs	$ 3,998,633	$ 4,040,009

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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 of unamortized debt discount (premium) and debt issuance 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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