Stock Issued During Period, Shares, Issued For Services, Convertible Preferred Shares

No definition available.

Name:	mdca_StockIssuedDuringPeriodSharesIssuedForServicesConvertiblePreferredShares
Namespace Prefix:	mdca_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3255-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from issuance of preferred stocks identified as being convertible into another form of financial instrument, typically the entity's common stock.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

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

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesIssuedPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

+ References

No definition available.

+ Details

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

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Basis of Presentation Basis of Presentation (Details) $ / shares in Units, $ in Millions			12 Months Ended
	Mar. 14, 2019 USD ($) $ / shares shares	Mar. 08, 2019 USD ($)	Dec. 31, 2018 reportable_segment
Segment Reporting Information [Line Items]
Number of reportable segments \| reportable_segment			4
Common Class A \| Subsequent Event [Member]
Segment Reporting Information [Line Items]
Price per share \| $ / shares	$ 3.50
Kingsdale Partners, LP \| Subsequent Event [Member]
Segment Reporting Information [Line Items]
Proceeds from sale of business		$ 50
Common Stock \| Common Class A \| Subsequent Event [Member]
Segment Reporting Information [Line Items]
Class A shares issued \| shares	14,285,714
Proceeds from sale of Class A shares	$ 50
Convertible Preference Shares \| Series 6 Convertible Preferred Shares [Member] \| Subsequent Event [Member]
Segment Reporting Information [Line Items]
Series 6 convertible preference shares issued \| shares	50,000
Proceeds from issuance of Series 6 convertible preference shares	$ 50