XML 83 R72.htm IDEA: XBRL DOCUMENT v3.19.1
Fair Value Measurements - Fair Value of Debt (Details) - Fixed rate debt - Level 2 - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Carrying Amount    
Fair Value, Balance Sheet Grouping, Financial Statement Captions    
Long-term debt, fair value $ 1,181,717 $ 690,001
Fair Value    
Fair Value, Balance Sheet Grouping, Financial Statement Captions    
Long-term debt, fair value $ 1,216,000 $ 674,000