v3.10.0.1

Subsequent Events (Details) - USD ($) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 14, 2019 | Feb. 01, 2019 | Jan. 31, 2019 | Jan. 18, 2019 | Nov. 14, 2018 | Aug. 14, 2018 | May 15, 2018 | Feb. 14, 2018 | Nov. 14, 2017 | Aug. 14, 2017 | May 15, 2017 | Feb. 14, 2017 | Nov. 14, 2016 | Aug. 12, 2016 | May 13, 2016 | Feb. 12, 2016 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,300,000,000 | $ 4,550,000,000 |
Proceeds from Issuance of Senior Long-term Debt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 496,705,000 | $ 1,142,997,000
Partners' Capital Account, Units, Unit-based Compensation (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 168,913 | 216,679 | 350,552
Units granted (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 302,487 |  |
Partners' Capital Account, Distribution Per Unit of Limited Partner Interest (in dollars per share) |  |  |  |  |  | $ 0.9775 | $ 0.9575 | $ 0.9375 | $ 0.9200 | $ 0.9050 | $ 0.8900 | $ 0.8725 | $ 0.8550 | $ 0.83750 | $ 0.8200 | $ 0.8025 | $ 0.7850 | $ 3.7925 | $ 3.5225 | $ 3.245
Total cash distributions |  |  |  |  |  | $ 223,061,000 | $ 218,497,000 | $ 213,933,000 | $ 209,940,000 | $ 206,362,000 | $ 202,942,000 | $ 198,951,000 | $ 194,961,000 | $ 190,769,000 | $ 186,783,000 | $ 182,797,000 | $ 178,808,000 | $ 865,431,000 | $ 803,216,000 | $ 739,157,000
6.55% Notes Due 2019 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 550,000,000 | $ 550,000,000 |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6.55% |  |
Management [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partners' Capital Account, Units, Unit-based Compensation (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 168,913 | 216,679 | 350,552
Director [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partners' Capital Account, Units, Unit-based Compensation (in shares) | [1] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,691 | 23,961 | 6,117
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partners' Capital Account, Units, Unit-based Compensation (in shares) |  |  | 208,268 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Units granted (in shares) |  |  | 347,473 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  |  | 3 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partners' Capital Account, Distribution Per Unit of Limited Partner Interest (in dollars per share) |  | $ 0.9975 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total cash distributions |  | $ 227,800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Four Point Two Percentage Notes Due Two Thousand Forty Five [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount |  |  |  |  | $ 500,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  |  | 4.85% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument, Notes At Price |  |  |  |  | 99.371% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Senior Long-term Debt |  |  |  |  | $ 492,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Management [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partners' Capital Account, Units, Unit-based Compensation (in shares) |  |  | 199,792 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Director [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Partners' Capital Account, Units, Unit-based Compensation (in shares) |  |  | 8,476 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unionized Employees Concentration Risk [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  | 24.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Collective Bargaining Agreement, Extension Term |  |  |  | 1 day |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
[1] | Limited partner units issued to settle the equity-based retainer paid to independent directors of our general partner.

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