XML 24 R13.htm IDEA: XBRL DOCUMENT v3.8.0.1
Operations and Organizaton (Details)
$ in Millions
9 Months Ended
Sep. 30, 2017
USD ($)
Description of the Business  
Senior Notes $ 300
Panhandle [Member] | General partnership  
Description of the Business  
General partnership interest 1.00%
Panhandle [Member] | Limited partner  
Description of the Business  
Limited partnership interest 99.00%