Debt Instrument, Basis Spread from Credit Rating

No definition available.

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- Definition

Debt Instrument, Covenant, Leverage Ratio

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Leverage Ratio, Temporary

+ 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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Balance Type:	debit
Period Type:	duration

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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Balance Type:	na
Period Type:	instant

- 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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Period Type:	duration

- Definition

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

+ References

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=34725769&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=6451184&loc=d3e28551-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

+ Details

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Balance Type:	na
Period Type:	instant

- 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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 22
-Article 5

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

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.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityCommitmentFeePercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the credit facility terminates, 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5

+ Details

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- Definition

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.

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ 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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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Debt - Additional Information (Detail) $ in Millions	3 Months Ended
Debt - Additional Information (Detail) $ in Millions	Mar. 31, 2016 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Proceeds from long-term debt	$ 394.0	$ 162.0
Senior Notes Two Point Seven Zero Percent Due Two Thousand Nineteen [Member]
Debt Instrument [Line Items]
Senior notes issued	$ 325.0		$ 325.0
Senior notes interest rate percentage	2.70%
Senior Notes Five Point Six Zero Percent Due Two Thousand Forty Four [Member]
Debt Instrument [Line Items]
Senior notes issued	$ 400.0		400.0
Senior notes interest rate percentage	5.60%
Senior Notes, 3.875% Due 2023 [Member]
Debt Instrument [Line Items]
Senior notes issued	$ 500.0		500.0
Senior notes interest rate percentage	3.875%
Maturity date	Mar. 15, 2023
Senior Notes, 2.50% Due 2017 [Member]
Debt Instrument [Line Items]
Senior notes issued	$ 500.0		500.0
Senior notes interest rate percentage	2.50%
Maturity date	Dec. 01, 2017
Senior Notes, 4.95% Due 2022 [Member]
Debt Instrument [Line Items]
Senior notes issued	$ 350.0		$ 350.0
Senior notes interest rate percentage	4.95%
Maturity date	Apr. 01, 2022
Senior Notes, 3.25% Due 2015 [Member]
Debt Instrument [Line Items]
Senior notes interest rate percentage	3.25%
Maturity date	Oct. 01, 2015
Eagle Ford System [Member] \| Senior Notes, 3.875% Due 2023 [Member]
Debt Instrument [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired			46.67%
Amended and Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			$ 1,000.0
Credit Agreement [Member]
Debt Instrument [Line Items]
Line of credit facility, maturity date	May 01, 2019
Unused capacity under the credit agreement	$ 922.0
Basis spread determined by credit rating	0.275%
Commitment fee percentage	0.23%
London Interbank Offered Rate (LIBOR) [Member] \| Credit Agreement [Member]
Debt Instrument [Line Items]
Variable rate basis spread	1.275%
Federal Funds Effective Swap Rate [Member] \| Credit Agreement [Member]
Debt Instrument [Line Items]
Variable rate basis spread	0.50%
London Interbank Offered Rate (LIBOR) Market Index [Member] \| Credit Agreement [Member]
Debt Instrument [Line Items]
Variable rate basis spread	1.00%
Credit Agreement [Member]
Debt Instrument [Line Items]
Letters of credit issued		$ 1.0
Letters of credit outstanding	$ 1.0		$ 1.0
Minimum [Member] \| Credit Agreement [Member]
Debt Instrument [Line Items]
Maximum leverage ratio	1.0
Temporary maximum leverage ratio post-acquisition	1.0
Maximum [Member] \| Credit Agreement [Member]
Debt Instrument [Line Items]
Maximum leverage ratio	5.0
Temporary maximum leverage ratio post-acquisition	5.5