Property and Equipment (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 73,598	$ 68,390
Less accumulated depreciation	(36,456)	(31,657)
Property and equipment, net	37,142	36,733
Depreciation	4,815	4,216	4,043
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,827	3,827
Building and improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	22,228	21,297
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	286	286
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	35,182	32,266
Office and computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	12,024	10,663
Motor vehicles
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 51	$ 51