v3.10.0.1

Long-Term Incentive Plan (Vested Unit Awards) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |  |  |
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Total Unit Award Accrual Number (in shares) | 317,037 | 266,028 | 361,711
Fair Value of Unit Awards on Vesting Date (in millions) | $ 22.1 | $ 19.9 | $ 22.6
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Vested | $ 18.1 | $ 18.9 | $ 27.4

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- Definition Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments, Other Than Options, Vested Number, As Adjusted + References No definition available. + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options. + References No definition available. + Details
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