Long-Term Obligations - Senior Notes - Additional Information (Detail) - Senior Notes [Member] - USD ($)	12 Months Ended
Dec. 31, 2016	Jul. 02, 2014
2021 [Member]
Debt Instrument [Line Items]
Debt instrument issuance date	Jun. 17, 2016
Debt instrument face amount	$ 400,000,000
Debt instrument maturity date	Jul. 15, 2021
Debt instrument redemption price percentage	104.75%
Debt instrument redemption end date	Jul. 15, 2018
Debt instrument redemption description	Equity offering
Debt instrument redemption period	90 days
Debt instrument redemption percentage maximum redeemable	40.00%
2021 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument redemption percentage minimum remaining	60.00%
2021 [Member] \| Senior Notes 2016 to 2018 [Member]
Debt Instrument [Line Items]
Debt instrument redemption period	12 months
Debt instrument redemption percentage maximum redeemable	10.00%
Debt instrument redemption percentage minimum remaining	103.00%
2021 [Member] \| Senior Notes 2016 to 2018 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument redemption end date	Jul. 15, 2016
2021 [Member] \| Senior Notes 2016 to 2018 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument redemption end date	Jul. 15, 2018
After July 15, 2020 [Member]
Debt Instrument [Line Items]
Debt instrument redemption price percentage	100.00%
Debt instrument redemption end date	Jul. 15, 2018
Senior Notes 2022 [Member]
Debt Instrument [Line Items]
Debt instrument issuance date	Jul. 01, 2014
Debt instrument face amount		$ 1,000,000,000
Debt instrument maturity date	Jul. 15, 2022
Debt instrument redemption price percentage	100.00%
Debt instrument redemption end date	Jul. 15, 2017
Senior Notes 2022 [Member] \| Equity Proceeds Redemption of Senior Notes 2022 [Member]
Debt Instrument [Line Items]
Debt instrument redemption price percentage	105.375%
Debt instrument redemption end date	Jul. 15, 2017
Debt instrument redemption description	Equity Offering
Debt instrument redemption period	90 days
Debt instrument redemption percentage maximum redeemable	40.00%
Debt instrument redemption percentage minimum remaining	60.00%

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

Date the debt instrument was issued, in CCYY-MM-DD format.

+ 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(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ 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(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

End date of debt instrument redemption period, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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- Definition

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

+ References

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- Definition

Debt instrument redemption description trigger event.

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- Definition

Debt instrument redemption percentage maximum redeemable.

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- Definition

Debt instrument redemption percentage minimum remaining.

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- Definition

Debt Instrument Redemption Period

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