XML 46 R35.htm IDEA: XBRL DOCUMENT v3.10.0.1
Goodwill and Franchise Value (Schedule of Franchise Value) (Details) - USD ($)
$ in Thousands
6 Months Ended 12 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Indefinite-lived Intangible Assets [Roll Forward]      
Balance $ 186,977 $ 184,268 $ 184,268
Additions through acquisitions     495
Adjustments to purchase price allocations 10,100 $ 2,214 2,200
Balance $ 197,111   $ 186,977