Critical and Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Critical and Significant Accounting Policies

Schedule of estimated useful lives of other plant and equipment for computation of depreciation using straight-line method

Buildings and improvements	5 to 25 years
Machinery and equipment	3 to 20 years
Furniture and fixtures	3 years

Exploration costs included in cost of product sold

	2015		2014		2013
Exploration Costs	$	1,778	$	3,101	$	2,409