Contingent Consideration (Details) (USD $)	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Contingent Consideration [Abstract]
Contingent consideration accrued, current	$ 1,200,000	$ 1,200,000		$ 1,600,000
Contingent consideration accrued, noncurrent	380,000	380,000		902,000
Payments of the liability-classified contingent consideration arrangements	$ 200,000	$ 1,188,000	$ 806,000