XML 52 R31.htm IDEA: XBRL DOCUMENT v3.19.3

Net Loss Per Share - Additional Information (Detail) - shares	3 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Potentially Dilutive Securities Outstanding [Line Items]
Common stock subject to repurchase or forfeiture	0	0

X

- Definition

Potentially Dilutive Securities Outstanding [Line Items]

+ References

No definition available.

+ Details

Name:	meip_PotentiallyDilutiveSecuritiesOutstandingLineItems
Namespace Prefix:	meip_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Number of shares of common stock subject to repurchase or cancellation determined by relating the portion of time within a reporting period that these shares have been outstanding to the total time in that period. Common stock subject to repurchase are outstanding common shares that are contingently returnable (that is, subject to recall).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e2646-109256

+ Details

Name:	us-gaap_WeightedAverageNumberOfSharesCommonStockSubjectToRepurchaseOrCancellation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration