XML 58 R48.htm IDEA: XBRL DOCUMENT v3.10.0.1
Share-based Compensation and Non-Qualified Deferred Compensation Plan (NQDC diversified share awards rollforward) (Details) - USD ($)
$ in Thousands
6 Months Ended 12 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Share-based Compensation [Abstract]      
Balance at December 31, 2017 $ 77,230    
Change in classification 10,635 $ 7,724  
Change in redemption value (976) 1,916  
Diversification of share awards (951) $ (2,627) $ (23,200)
Balance at June 30, 2018 $ 85,938   $ 77,230