Net Loss Per Share - Computation of Net Loss Per Share, Basic and Diluted (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Numerator:
Net loss attributable to New Relic	$ (8,336)	$ (14,691)	$ (13,951)	$ (30,625)
Denominator:
Weighted-average shares used to compute net loss per share, basic and diluted (in shares)	56,706	54,699	56,446	54,201
Net loss attributable to New Relic per share - basic and diluted (in usd per share)	$ (0.15)	$ (0.27)	$ (0.25)	$ (0.57)