Intangible Assets (Details Textual) (USD $)	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Goodwill [Line Items]
Goodwill	$ 88,753,000	$ 84,036,000	$ 72,936,000
Intangible Assets (Textual) [Abstract]
Aggregate amortization expense, estimated 2013	6,100,000
Aggregate amortization expense, estimated 2014	5,800,000
Aggregate amortization expense, estimated 2015	5,700,000
Aggregate amortization expense, estimated 2016	4,800,000
Aggregate amortization expense, estimated 2017	3,900,000
Advanced Material Technologies [Member]
Goodwill [Line Items]
Goodwill	86,900,000
Beryllium And Composites [Member]
Goodwill [Line Items]
Goodwill	$ 1,900,000