Aggregate value used to determine number of shares underlying the warrant and issuable upon exercise of warrants.

No definition available.

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Namespace Prefix:	meg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value of warrants.

+ References

No definition available.

+ Details

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Namespace Prefix:	meg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Date the warrants or rights are exercisable, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

+ Details

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Period Type:	duration

- Definition

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

+ References

+ Details

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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

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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

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=109262497&loc=d3e20148-110875

+ Details

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Balance Type:	debit
Period Type:	duration

- 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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- Details

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- Details

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- Details

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Warrant Options - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Apr. 30, 2020	Apr. 13, 2020	Dec. 31, 2019	Oct. 31, 2018	Oct. 19, 2018
Class Of Warrant Or Right [Line Items]
Period between issuance and expiration of outstanding warrant					10 years
Redeemable Series A-1 Preferred Stock
Class Of Warrant Or Right [Line Items]
Warrants to purchase common stock							534,240	534,240
Warrant exercise price per share							$ 0.01
Period between issuance and expiration of outstanding warrant							10 years
Fair value of warrants		$ 16.9				$ 16.9
Warrants exercised in full for cash, date		Jul. 30, 2020
Redeemable Series A-1 Preferred Stock \| Other Income (Expense)
Class Of Warrant Or Right [Line Items]
Fair value adjustment of warrants	$ 1.5		$ 1.5
Redeemable Series A-2 Preferred Stock
Class Of Warrant Or Right [Line Items]
Warrants to purchase common stock				1,351,960
Warrant exercise price per share				$ 0.01
Period between issuance and expiration of outstanding warrant				10 years
Fair value of warrants		$ 30.1
Warrants exercised in full for cash, date		Jul. 30, 2020
Aggregate value to determine number of shares underlying the warrant and issuable upon exercise of warrants		$ 30.0