Supplemental Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash paid during the period for:
Interest	$ 1,103	$ 1,559	$ 2,788
Income taxes	7,134	6,999	3,202
Non-cash transactions:
Barter revenue	3,855	4,188	4,369
Barter expense	3,844	3,894	4,138
Acquisition of property and equipment	$ 104	$ 99	$ 286