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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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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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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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Debt - Additional Information (Detail) - USD ($)			3 Months Ended	9 Months Ended
Debt - Additional Information (Detail) - USD ($)	Sep. 30, 2017	Aug. 31, 2017	Sep. 30, 2017	Sep. 30, 2017	Oct. 01, 2016	Dec. 31, 2016
Debt Instrument [Line Items]
Proceeds from issuance of long-term debt				$ 744,700,000	$ 0
Loss on extinguishment of debt				21,200,000	0
Prior credit agreement payments				468,700,000	$ 15,600,000
Long-term debt, gross	$ 1,975,000,000		$ 1,975,000,000	$ 1,975,000,000		$ 1,943,700,000
Credit Agreement — Revolving Credit Facility \| Minimum
Debt Instrument [Line Items]
Line of credit facility, facility fee				0.125%
Credit Agreement — Revolving Credit Facility \| Maximum
Debt Instrument [Line Items]
Line of credit facility, facility fee				0.30%
Senior notes \| 3.8% Senior Notes due 2027 (2027 Notes) (1)
Debt Instrument [Line Items]
Debt instrument, face amount		$ 750,000,000
Debt instrument, interest rate, stated percentage	3.80%	3.80%	3.80%	3.80%
Debt redemption price, percentage		99.294%
Debt interest rate, effective percentage	3.885%	3.885%	3.885%	3.885%
Proceeds from issuance of long-term debt		$ 744,700,000
Debt issuance costs		6,000,000
Senior notes \| 3.8% Senior Notes due 2027 (2027 Notes) (1) \| Prior to June 15, 2027
Debt Instrument [Line Items]
Debt redemption price, percentage	100.00%
Senior notes \| 3.8% Senior Notes due 2027 (2027 Notes) (1) \| On or after June 15, 2027
Debt Instrument [Line Items]
Debt redemption price, percentage	100.00%
Senior notes \| 4.75% Senior Notes due 2023 (2023 Notes)
Debt Instrument [Line Items]
Debt instrument, face amount		$ 500,000,000
Debt instrument, interest rate, stated percentage	4.75%		4.75%	4.75%		4.75%
Debt redemption price, percentage		100.00%
Make-whole premium		$ 17,000,000
Loss on extinguishment of debt			$ 21,200,000	$ 21,200,000
Long-term debt, gross	$ 0		0	0		$ 500,000,000
Credit agreement \| Credit Agreement — Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt issuance costs		5,700,000
Line of credit facility, maximum borrowing capacity		1,750,000,000.00
Borrowings outstanding under revolving credit facility	$ 0		$ 0	$ 0		$ 0
Credit agreement \| Credit Agreement — Revolving Credit Facility \| Prior Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		1,250,000,000.00
Credit agreement \| Credit Agreement — Term Loan Facility \| Prior Term Loan Facility
Debt Instrument [Line Items]
Debt instrument, face amount		500,000,000.0
Credit agreement \| Credit Agreement — Term Loan Facility \| Term Loan Facility
Debt Instrument [Line Items]
Debt instrument, face amount		250,000,000.0
Debt instrument, interest rate, stated percentage	2.70%		2.70%	2.70%		2.105%
Prior credit agreement payments		$ 453,100,000
Long-term debt, gross	$ 250,000,000		$ 250,000,000	$ 250,000,000		$ 468,700,000