Debt - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Total long-term debt	$ 2,430	$ 2,188
Fair value of long-term debt obligations	$ 2,440
Total leverage ratio	343.00%
Revolving Credit Facility, variable, due 2021
Debt Instrument [Line Items]
Debt instrument effective interest rate	2.61%
Available revolving credit facility	$ 187
Revolving credit facility, net	245
Letters of Credit	$ 18
Maturity date of revolving credit borrowings	2021-09
Required senior secured leverage ratio	550.00%
Achieved senior secured leverage ratio	194.00%
Senior secured leverage ratio for applicable margin reduction	400.00%
Total leverage ratio for applicable margin reduction	400.00%
Basis point reduction to applicable margin, resulting from total leverage ratio below minimum	0.25%
Total leverage ratio for commitment fee reduction	350.00%
Basis point reduction to commitment fee, resulting from total leverage ratio below minimum	0.125%
Additional basis point reduction to applicable margin, resulting from total leverage ratio below minimum	0.25%
Revolving Credit Facility, variable, due 2021 \| LIBOR
Debt Instrument [Line Items]
Applicable margin over base rate	1.75%
Revolving Credit Facility, variable, due 2021 \| LIBOR \| Minimum
Debt Instrument [Line Items]
Debt instrument, floor rate		0.75%
Revolving Credit Facility, variable, due 2021 \| greater of the prime lending rate or federal funds
Debt Instrument [Line Items]
Applicable margin over base rate	0.50%
Revolving Credit Facility, variable, due 2021 \| greater of the prime lending rate or federal funds \| Minimum
Debt Instrument [Line Items]
Debt instrument, floor rate	1.75%
5.0% Senior Notes due 2024
Debt Instrument [Line Items]
Debt instrument maturity month and year	2024-09
Debt instrument, interest rate, stated percentage	5.00%
Total long-term debt	$ 1,000	$ 1,000
Senior Secured Credit Facility Term B-3 Loan, variable due 2022
Debt Instrument [Line Items]
Debt instrument maturity month and year	2022-09
Total long-term debt	$ 1,185	$ 1,188
Debt financing fees	$ 1
Debt instrument effective interest rate	2.99%
Principal payments on term loans	$ 3
Senior Secured Credit Facility Term B-3 Loan, variable due 2022 \| Minimum
Debt Instrument [Line Items]
Applicable margin over base rate	1.00%	1.75%
Senior Secured Credit Facility Term B-3 Loan, variable due 2022 \| LIBOR
Debt Instrument [Line Items]
Applicable margin over base rate	2.00%
Senior Secured Credit Facility Term B-3 Loan, variable due 2022 \| LIBOR \| Minimum
Debt Instrument [Line Items]
Debt instrument, floor rate	1.00%
Senior Secured Credit Facility Term B-3 Loan, variable due 2022 \| greater of the prime lending rate or federal funds \| Minimum
Debt Instrument [Line Items]
Applicable margin over base rate	1.00%
Debt instrument, floor rate	1.00%
Senior Secured Credit Facility Term B-3 Loan, variable due 2022 \| Federal Funds Rate
Debt Instrument [Line Items]
Applicable margin over base rate	0.50%

Achieved senior secured leverage ratio.

No definition available.

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- Definition

Achieved Total Leverage Ratio

+ References

No definition available.

+ Details

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- Definition

Additional interest rate reduction basis points resulting from net leverage ratio below minimum.

+ References

No definition available.

+ Details

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- Definition

Commitment Fee Reduction Resulting from Total Leverage Ratio Below Minimum

+ References

No definition available.

+ Details

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- Definition

Debt Instrument Floor Rate

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Maturity, Month and Year

+ References

No definition available.

+ Details

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- Definition

Interest Rate Reduction, Basis Points Resulting from Total Leverage Ratio Below Minimum

+ References

No definition available.

+ Details

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- Definition

Date when the revolving debt instrument is scheduled to mature.

+ References

No definition available.

+ Details

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- Definition

Minimum senior secured leverage ratio required to achieve certain reductions.

+ References

No definition available.

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- Definition

Required senior secured leverage ratio.

+ References

No definition available.

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- Definition

Total Leverage Ratio Threshold For Commitment Fee Reduction

+ References

No definition available.

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- Definition

Total Leverage Ratio Threshold for Rate Reduction

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the required periodic payment applied to principal.

+ References

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3291-108585

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