Inventories (Notes)

9 Months Ended

Dec. 31, 2016

The components of inventories consist of the following (amounts in thousands):



	December 31, 2016		March 31, 2016
Raw materials	$	14,733	$	12,179
Work in process	267,399		208,283
Finished goods	137,486		86,353
Total inventories	$	419,618	$	306,815

Inventories are valued at the lower of cost or market using the first-in, first-out method. Inventory impairment charges establish a new cost basis for inventory and charges are not subsequently reversed to income even if circumstances later suggest that increased carrying amounts are recoverable.