v3.20.1

Long-Term Incentive Plan (Equity-Based Incentive Compensation Expense) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Long Term Incentive Plan [Line Items] |  |  |
Allocation of LTIP expense on Consolidated Statements of Income | $ 24,012 | $ 32,053 | $ 20,641
Performance Shares [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Allocation of LTIP expense on Consolidated Statements of Income | 17,920 | 28,728 | 17,823
Time-Based Awards [Member] |  |  |
Long Term Incentive Plan [Line Items] |  |  |
Allocation of LTIP expense on Consolidated Statements of Income | $ 6,092 | $ 3,325 | $ 2,818

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