v3.10.0.1

Long-Term Incentive Plan (Equity-Based Incentive Compensation Expense) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Long Term Incentive Plan [Line Items] |  |  |
Allocation of LTIP expense on Consolidated Statements of Income | $ 32,053 | $ 20,641 | $ 19,358
G&A Expense [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Allocation of LTIP expense on Consolidated Statements of Income | 31,788 | 20,463 | 19,204
Operating Expenses [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Allocation of LTIP expense on Consolidated Statements of Income | 265 | 178 | 154
Performance Shares [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Allocation of LTIP expense on Consolidated Statements of Income | 28,728 | 17,823 | 17,106
Time-Based Awards [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Allocation of LTIP expense on Consolidated Statements of Income | $ 3,325 | $ 2,818 | $ 2,252

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