Inventories (Tables)

12 Months Ended

Dec. 31, 2014

Inventory Disclosure [Abstract]

Summary of Inventories

Inventories on the Consolidated Balance Sheets are summarized as follows:

	December 31,
(Thousands)	2014		2013
Principally average cost:
Raw materials and supplies	$	39,559	$	39,201
Work in process	155,377		152,645
Finished goods	37,473		40,954
Net inventories	$	232,409	$	232,800