Revenue Recognition - Impact on the Condensed Consolidated Financial Statements (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Apr. 01, 2018	Mar. 31, 2018
Assets
Deferred contract acquisition costs, current	$ 23,409		$ 23,409			$ 0
Deferred contract acquisition costs, non-current	22,731		22,731			0
Liabilities:
Deferred revenue, current	181,764		181,764		$ 188,860	189,633
Deferred revenue, non-current	8,917		8,917		1,182	649
Stockholders' equity:
Accumulated deficit	(278,622)		(278,622)			$ (305,484)
Income Statement [Abstract]
Revenue	114,896	$ 84,685	223,117	$ 164,783
Sales and marketing	61,142	51,261	118,630	100,622
Loss from operations	(5,535)	(14,841)	(9,166)	(31,289)
Net loss attributable to New Relic	$ (8,336)	$ (14,691)	$ (13,951)	$ (30,625)
Net loss per share, basic and diluted (in usd per share)	$ (0.15)	$ (0.27)	$ (0.25)	$ (0.57)
Statement of Cash Flows [Abstract]
Depreciation and amortization			$ 24,823	$ 11,553
Deferred contract acquisition costs			(17,415)	$ 0
Net cash provided by operating activities			58,214
Balances without adoption of ASC 606
Assets
Deferred contract acquisition costs, current	$ 0		0
Deferred contract acquisition costs, non-current	0		0
Liabilities:
Deferred revenue, current	182,462		182,462
Deferred revenue, non-current	8,837		8,837
Stockholders' equity:
Accumulated deficit	(325,395)		(325,395)
Income Statement [Abstract]
Revenue	114,483		222,736
Sales and marketing	65,009		124,207
Loss from operations	(9,815)		(15,124)
Net loss attributable to New Relic	$ (12,616)		$ (19,909)
Net loss per share, basic and diluted (in usd per share)	$ (0.22)		$ (0.35)
Statement of Cash Flows [Abstract]
Depreciation and amortization			$ 12,985
Deferred contract acquisition costs			0
Net cash provided by operating activities			58,214
Effect of Change Higher (Lower) | Accounting Standards Update 2014-09
Assets
Deferred contract acquisition costs, current	$ 23,409		23,409
Deferred contract acquisition costs, non-current	22,731		22,731
Liabilities:
Deferred revenue, current	(698)		(698)
Deferred revenue, non-current	80		80
Stockholders' equity:
Accumulated deficit	46,773		46,773		$ 40,800
Income Statement [Abstract]
Revenue	413		381
Sales and marketing	(3,867)		(5,577)
Loss from operations	4,280		5,958
Net loss attributable to New Relic	$ 4,280		$ 5,958
Net loss per share, basic and diluted (in usd per share)	$ 0.07		$ 0.10
Statement of Cash Flows [Abstract]
Depreciation and amortization			$ 11,838
Deferred contract acquisition costs			(17,415)
Net cash provided by operating activities			$ 0