Fair Value of Financial Instruments (Detail) $ in Thousands	Sep. 30, 2021 USD ($)
Fair Value Disclosures [Abstract]
Estimated fair value of Long-term debt (including current maturities)	$ 2,913,841
Gross amount of company's long term debt	$ 2,875,468

Face (par) amount of debt instrument at time of issuance.

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Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant