Supplemental Cash Flow Information (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash paid during the period for:
Interest	$ 874us-gaap_InterestPaid	$ 1,103us-gaap_InterestPaid	$ 1,559us-gaap_InterestPaid
Income taxes	7,319us-gaap_IncomeTaxesPaid	7,134us-gaap_IncomeTaxesPaid	6,999us-gaap_IncomeTaxesPaid
Non-cash transactions:
Barter revenue	3,844	3,855	4,188
Barter expense	3,636	3,844	3,894
Acquisition of property and equipment	$ 91	$ 104	$ 99

Total expense recognized from advertising barter transactions for each income statement presented.

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Total revenue recognized from advertising barter transactions for each income statement presented.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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