ALLOWANCE FOR DOUBTFUL ACCOUNTS:	6 Months Ended
	Sep. 30, 2019
SEC Schedule, 12-09, Valuation and Qualifying Accounts [Abstract]
ALLOWANCE FOR DOUBTFUL ACCOUNTS:	ALLOWANCE FOR DOUBTFUL ACCOUNTS: Trade accounts receivable are presented net of allowances for doubtful accounts, returns and credits of $4.2 million at September 30, 2019 and $3.0 million at March 31, 2019.