Net Periodic Benefit Cost-Defined Benefit Plans (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Net periodic benefit cost of the domestic non-contributory defined benefit plan
Service cost	$ 41,000	$ 17,000
Interest cost	189,000	193,000
Expected return on plan assets	(262,000)	(251,000)
Amortization of net loss	39,000	39,000
Net periodic benefit cost	7,000	$ (2,000)
Expected contribution to Pension Plan in 2015 (minimum)			$ 500,000
Employer contributions made to the defined benefit plan	250,000
Anticipated additional contributions anticipated during the remainder of 2015 (at least)	$ 250,000