XML 23 R53.htm IDEA: XBRL DOCUMENT v2.4.0.8
Variable Interest Entities - Royalty Trusts - Distributions (Details) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 6 Months Ended
Jun. 30, 2013
Jun. 30, 2012
Jun. 30, 2013
Jun. 30, 2012
Variable Interest Entity        
Distributions to third-party unitholders     $ 98,716 $ 76,801
Royalty Trusts
       
Variable Interest Entity        
Total distributions 68,449 65,948 144,810 118,017
Distributions to third-party unitholders $ 47,459 $ 44,062 $ 98,716 $ 76,801