v3.10.0.1

Long-Term Incentive Plan (Total Non-Vested Unit Awards) (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Long Term Incentive Plan [Line Items] |  |  |
Non-vested units (in shares) |  | 501,403 | 417,172
Adjustment to Unit Awards in Anticipation of Achieving Above- Target Financial Results (in shares) |  | 159,232 |
Total Unit Award Accrual (in shares) |  | 660,635 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized | [1] | $ 24.3 |
Performance Shares [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Non-vested units (in shares) |  | 390,015 | 356,068
Time-Based Awards [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Non-vested units (in shares) |  | 111,388 | 61,104
2017 Awards [Member] | Performance Shares [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Non-vested units (in shares) |  | 176,924 |
Adjustment to Unit Awards in Anticipation of Achieving Above- Target Financial Results (in shares) |  | 159,232 |
Total Unit Award Accrual (in shares) |  | 336,156 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized | [1] | $ 9.0 |
Two Thousand Eighteen Awards [Member] | Performance Shares [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Non-vested units (in shares) |  | 213,091 |
Adjustment to Unit Awards in Anticipation of Achieving Above- Target Financial Results (in shares) |  | 0 |
Total Unit Award Accrual (in shares) |  | 213,091 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized | [1] | $ 10.5 |
Retention Awards Vesting 2019 [Member] | Time-Based Awards [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Non-vested units (in shares) |  | 31,835 |
Adjustment to Unit Awards in Anticipation of Achieving Above- Target Financial Results (in shares) |  | 0 |
Total Unit Award Accrual (in shares) |  | 31,835 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized | [1] | $ 0.9 |
Retention Awards Vesting 2020 [Member] | Time-Based Awards [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Non-vested units (in shares) |  | 79,553 |
Adjustment to Unit Awards in Anticipation of Achieving Above- Target Financial Results (in shares) |  | 0 |
Total Unit Award Accrual (in shares) |  | 79,553 |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized | [1] | $ 3.9 |
[1] | Unrecognized compensation expense will be recognized over the remaining vesting period of the awards.

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- Definition Adjustment To Unit Awards + References No definition available. + Details
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- Definition Long Term Incentive Plan [Line Items] + References No definition available. + Details
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- Definition Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Total Unit Award Accrual Number + References No definition available. + Details
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- Definition Unrecognized cost of unvested share-based compensation awards. + 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 (i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + 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 (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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