Contingencies - Accrual for Environmental Remediation (Details)	12 Months Ended
	Dec. 31, 2015 USD ($)
Environmental remediation accrual at December 31, 2014	$ 265,876
Payments	(186,000)
Environmental remediation accrual at December 31, 2015	80,947
Fremont, NC
Environmental remediation accrual at December 31, 2014	260,000
Payments	(180,000)
Environmental remediation accrual at December 31, 2015	80,000
Bridgeport, CT
Environmental remediation accrual at December 31, 2014	6,000
Payments	$ (6,000)