Income Taxes (Details 1)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of the federal statutory and effective income tax rate
U.S. Federal statutory rate	35.00%	35.00%	35.00%
State and local income taxes, net of federal tax effect	2.30%	(0.40%)	1.70%
Effect of excess of percentage depletion over cost depletion	(10.00%)	(10.60%)	(7.10%)
Manufacturing production deduction	(0.80%)	(3.30%)	(0.90%)
Foreign Rate Differential	(3.40%)	(5.90%)	(4.20%)
Tax Cuts and Jobs Act Impact	47.10%	0.00%	0.00%
Research and developmental tax credit	(2.60%)	(6.60%)	(1.60%)
Foreign Tax Credit	(1.10%)	(28.10%)	(4.80%)
Foreign Repatriation	1.30%	13.70%	5.90%
Incremental fixed asset basis	(3.40%)	(0.00%)	(0.00%)
Adjustment to unrecognized tax benefits	2.80%	3.20%	(1.10%)
Stock Compensation - excess tax benefits	(1.90%)	(0.00%)	(0.00%)
Valuation allowance	2.40%	0.10%	(0.90%)
Other items	0.80%	1.20%	2.90%
Effective tax rate	68.50%	(1.70%)	24.90%