Business Acquisitions Sales and Earnings (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Business Acquisition [Line Items]
Revenues from external customers									$ 79,017	$ 109,338	$ 97,644
Net income / (loss)									(25,803)	7,865	5,078
Basic (in dollars per share)	$ (0.75)	$ 0.02	$ 0.05	$ (0.03)	$ (0.05)	$ 0.16	$ 0.06	$ 0.00	$ (0.78)	$ 0.23	$ 0.12
Diluted (in dollars per share)	$ (0.75)	$ 0.02	$ 0.05	$ (0.03)	$ (0.05)	$ 0.15	$ 0.05	$ 0.00	$ (0.01)	$ 0.23	$ 0.12
PECO and FGC Acquisitions [Member]
Business Acquisition [Line Items]
Revenues from external customers									4,193
Net income / (loss)									$ (120)
Basic (in dollars per share)									$ 0.00
Diluted (in dollars per share)									$ 0.00