Acquisitions Acquisitions (Pro Forma) (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Business Acquisition [Line Items]
Revenue of acquiree since acquisition date, actual	$ 98,600,000	$ 33,500,000	$ 180,600,000	$ 41,200,000
Earnings or loss of acquiree since acquisition date, actual	5,300,000	1,500,000	10,900,000	2,300,000
2013 [Member]
Business Acquisition [Line Items]
Pro Forma Revenue		377,327,000		1,099,439,000
Pro Forma Net income (Loss)		13,199,000		37,923,000
2014 [Member]
Business Acquisition [Line Items]
Pro Forma Revenue	529,169,000	469,972,000	1,546,672,000	1,288,597,000
Pro Forma Net income (Loss)	$ 14,698,000	$ 15,509,000	$ 44,452,000	$ 41,269,000