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Fair Value Measurements - Fair Value by Balance Sheet Grouping (Details) - Fair Value Measurements Using Level 3 - USD ($)
$ in Thousands
Mar. 31, 2020
Dec. 31, 2019
Carrying Amount    
Liabilities    
Carrying value of debt $ 1,429,768 $ 1,311,977
Fair Value    
Liabilities    
Fair value of debt $ 1,312,977 $ 1,276,589