Class Of Warrant Or Right Expired In Period

No definition available.

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Namespace Prefix:	mgen_
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Balance Type:	na
Period Type:	duration

- Definition

Class of Warrant or Right, Fair Value Per Share

+ References

No definition available.

+ Details

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Namespace Prefix:	mgen_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_ClassOfWarrantOrRightLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_WarrantsAndRightsOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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Balance Type:	na
Period Type:	instant

- Details

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- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=mgen_EquityclassifiedWarrantsIssuedFebruary2020Member
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- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=mgen_EquityclassifiedWarrantsMember
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- Details

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- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=mgen_EquityclassifiedWarrantsIssuedNovember2017Member
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WARRANTS - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	3 Months Ended
	Feb. 17, 2020	Jun. 30, 2019	Mar. 31, 2020	Feb. 29, 2020	Dec. 31, 2019	Dec. 31, 2017
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)			7,535,815		46,522
Warrant exercise price (in usd per share)			$ 1.13		$ 17.93
Expired (in shares)			10,707
2017 Merger
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)			11,718		11,718
Warrant exercise price (in usd per share)			$ 8.53
Expected life (years)			10 years
Warrant liability			$ 0.1
Warrant, fair value per share (in usd per share)			$ 8.53
Issued February 2020
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)			7,500,000	7,500,000	0
Warrant exercise price (in usd per share)			$ 1.10	$ 1.10
Expected life (years)				5 years
Equity-classified warrants
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)			7,524,097		34,804
Warrant exercise price (in usd per share)			$ 1.12
Acquired February 2017
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)			0		10,707	13,534
Warrant exercise price (in usd per share)			$ 0.00			$ 52.50
Expired (in shares)	10,707	2,827
Issued November 2017
Class of Warrant or Right [Line Items]
Warrants outstanding (in shares)			24,097		24,097
Warrant exercise price (in usd per share)			$ 7.15
Expected life (years)			7 years