Inventories: (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Inventory Disclosure [Abstract]
Raw material	$ 23,066	$ 21,867
Work in process	4,188	2,749
Finished goods	10,994	9,835
Total	$ 38,248	$ 34,451	[1]

[1] December 31, 2013 balances were derived from audited consolidated financial statements.