Fair Value of Financial Instruments Contingent Consideration (Tables) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Sep. 30, 2013	Jun. 30, 2014 Fair Value, Inputs, Level 3 [Member]	Mar. 31, 2014 Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Fair Value, Inputs, Level 3 [Member]	Jun. 30, 2013 Fair Value, Inputs, Level 3 [Member]	Mar. 31, 2013 Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2012 Fair Value, Inputs, Level 3 [Member]
Site Contingency [Line Items]
Business Combination, Contingent Consideration, Liability	$ 900	$ 1,100	$ 900	$ 1,100			$ 5,611	$ 5,344	$ 4,297	$ 4,142	$ 3,987
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	267	155	534	310
Contingent Consideration Classified as Equity, Fair Value Disclosure	$ 5,878		$ 5,878		$ 5,344	$ 5,878		$ 5,344