Leases - Prepaid Leases (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Operating Leased Assets [Line Items]
Net book value of asset	$ 76,135,000	$ 75,570,000
People's Republic of China [Member]
Operating Leased Assets [Line Items]
Number of factories	2
Guangzhou
Operating Leased Assets [Line Items]
Net book value of prepaid lease	1,400,000
Prepaid lease assets, remaining amortization period	15 years
Guangzhou | Buildings on Prepaid Land
Operating Leased Assets [Line Items]
Net book value of asset	13,400,000
Asset, remaining depreciable period	17 years
Yangzhou
Operating Leased Assets [Line Items]
Net book value of prepaid lease	2,800,000
Prepaid lease assets, remaining amortization period	44 years
Yangzhou | Buildings on Prepaid Land
Operating Leased Assets [Line Items]
Net book value of asset	$ 23,600,000
Asset, remaining depreciable period	25 years