Inventories (Notes)

6 Months Ended

Sep. 30, 2016

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



	September 30, 2016		March 31, 2016
Raw materials	$	15,227	$	12,179
Work in process	292,536		208,283
Finished goods	116,927		86,353
Total inventories	$	424,690	$	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.