Fair Value Measurements - Narrative (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other Asset Impairment Charges	$ 55,000	$ 103,000	$ 8,500,000
Goodwill impairment charge	0	0	8,344,000
Impairment of cost-method investment	2,368,000	0	0
Other Long-term Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration liability	5,900,000
Accrued Liabilities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration liability	$ 723,000