Long-Term Incentive Plan (Narrative) (Details) shares in Millions	12 Months Ended
Dec. 31, 2015 shares
Long Term Incentive Plan [Line Items]
Limited partners' capital account, units issued	9.4
Limited partner unitholders, units remaining available	1.0
Performance Shares [Member]
Long Term Incentive Plan [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Equity Based Compensation, Award Payout Percentage, Minimum	0.00%
Equity Based Compensation, Award Payout Percentage, Maximum	200.00%
Equity Based Compensation Award Payout Fluctuation Of Award Market	50.00%
2013 and Prior Awards [Member]
Long Term Incentive Plan [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Payout Calculation Established Financial Metric	80.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Payout Calculation Established Financial Metric and Personal Performance	20.00%

Equity Based Compensation Award Payout Fluctuation Of Award Market

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Equity Based Compensation, Award Payout Percentage, Maximum

+ References

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Equity Based Compensation, Award Payout Percentage, Minimum

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- Definition

Long Term Incentive Plan [Line Items]

+ References

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Payout Calculation Established Financial Metric

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No definition available.

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Payout Calculation Established Financial Metric and Personal Performance

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- Definition

The maximum number of shares authorized for issuance under the deferred compensation arrangement as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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