Acquisitions (Narrative) (Details) (USD $)	3 Months Ended								12 Months Ended			0 Months Ended		9 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 22, 2012	Apr. 08, 2013	Dec. 31, 2013
Business Acquisition [Line Items]
Gain on reduction of earnout liability									$ 0	$ 195,000	$ 0
Holdback payment related to acquisition									(231,000)	0	0
Transaction costs									176,000	257,000	284,000
Net sales	317,087,000	354,060,000	344,586,000	279,983,000	305,190,000	328,468,000	314,653,000	248,726,000	1,295,716,000	1,197,037,000	942,398,000
Selling, general and administrative expenses [Member]
Business Acquisition [Line Items]
Holdback payment related to acquisition									(231,000)
TBSG [Member]
Business Acquisition [Line Items]
Date of acquisition												Dec. 22, 2012
Assets and liabilities purchased												6,800,000
Earnout advance												900,000
Earnout advance interest rate												0.09
Net earnout liability	0								0
Commonwealth Acquisition Holdings, LLC [Member] | Chesapeake [Member]
Business Acquisition [Line Items]
Date of acquisition													Apr. 08, 2013
Acquisition purchase price, including holdback													2,600,000
Initial holdback amount													200,000
Business combination, net sales of acquiree since acquisition date, actual									7,900,000					7,900,000
Total assets acquired													3,100,000
Total liabilities assumed													1,400,000
Goodwill													700,000
Commonwealth Acquisition Holdings, LLC [Member] | Chesapeake [Member] | Selling, general and administrative expenses [Member]
Business Acquisition [Line Items]
Transaction costs										200,000
Customer relationships [Member] | Commonwealth Acquisition Holdings, LLC [Member] | Chesapeake [Member]
Business Acquisition [Line Items]
Intangible assets acquired													$ 1,200,000