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Acquisition (Fair Values of Assets Acquired and Liabilities Assumed) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 16, 2014
Business Acquisition [Line Items]
Goodwill	$ 6,253us-gaap_Goodwill	$ 6,253us-gaap_Goodwill	$ 0us-gaap_Goodwill
Weston Products, LLC
Business Acquisition [Line Items]
Accounts receivable				6,100
Inventory				5,113
Other current assets				624
Property, plant and equipment				590
Intangible assets				10,100
Total assets acquired				22,527
Current liabilities acquired				3,367
Net assets acquired				19,160
Purchase price				25,413
Goodwill				$ 6,253