Fair Value Measurements - Carrying Amounts and Fair Values of Company's Amended and Restated Senior Credit Facilities and Contingent Consideration Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other long-term debt	$ 3,625	$ 4,821
Carrying Amount [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other long-term debt	3,625	4,821
Derivative instruments	84,584	68,915
Carrying Amount [Member] \| Amended and Restated Senior Credit Facility [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Secured	1,175,437	1,668,062
Carrying Amount [Member] \| 6.125% Senior Notes Due 2021 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes		149,254
Carrying Amount [Member] \| 5.125% Senior Notes Due 2022 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes		297,761
Carrying Amount [Member] \| 5.625% Senior Notes Due 2023 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes	646,344	644,771
Carrying Amount [Member] \| 6.500% Senior Notes due 2024 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes	385,636	384,430
Carrying Amount [Member] \| 5.500% Senior Notes due 2028 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes	443,139
Carrying Amount [Member] \| 5.000% Senior Notes due 2029 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes	468,245
Fair Value [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Other long-term debt	3,625	4,821
Derivative instruments	84,584	68,915
Fair Value [Member] \| Amended and Restated Senior Credit Facility [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Amended and Restated Senior Credit Facility	1,175,437	1,668,062
Fair Value [Member] \| 6.125% Senior Notes Due 2021 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes		149,441
Fair Value [Member] \| 5.125% Senior Notes Due 2022 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes		299,994
Fair Value [Member] \| 5.625% Senior Notes Due 2023 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes	647,960	655,249
Fair Value [Member] \| 6.500% Senior Notes due 2024 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes	393,850	$ 398,366
Fair Value [Member] \| 5.500% Senior Notes due 2028 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes	475,931
Fair Value [Member] \| 5.000% Senior Notes due 2029 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Senior Notes	$ 499,852

Derivative instruments at carrying value net.

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- Definition

Other long term debt fair value.

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Aggregate net fair value of all derivative instruments designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

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Fair value portion of notes payable.

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Amount of long-term debt classified as other.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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