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

Exercise of redeemable A-1 preferred stock warrant shares.

+ References

No definition available.

+ Details

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- 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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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

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- 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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- Definition

The number of new shares issued in the conversion of stock in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4332-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4313-108586

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=121583591&loc=d3e4304-108586

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Balance Type:	na
Period Type:	duration

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
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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- 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
	Jul. 30, 2020	Jul. 27, 2020	Mar. 31, 2021	Apr. 30, 2020	Apr. 13, 2020	Mar. 31, 2020	Oct. 19, 2018
Class Of Warrant Or Right [Line Items]
Period between issuance and expiration of outstanding warrant					10 years
Share price			$ 37.61			$ 31.60
Redeemable Series A-1 Preferred Stock
Class Of Warrant Or Right [Line Items]
Warrants to purchase common stock							534,240
Warrant exercise price per share							$ 0.01
Period between issuance and expiration of outstanding warrant							10 years
Warrants exercised in full for cash, date			Jul. 30, 2020
Redeemable Series A-1 Preferred Stock \| Common Stock
Class Of Warrant Or Right [Line Items]
Warrant exercise price per share	$ 0.01
Exercise of redeemable A1 preferred stock warrant shares	2,534,239
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
Aggregate value to determine number of shares underlying the warrant and issuable upon exercise of warrants				$ 30.0
Convertible And Redeemable Series A-2 Preferred Stock
Class Of Warrant Or Right [Line Items]
Warrants to purchase common stock		1,999,999
Share price		$ 15.00
Increase of shares		648,039