Debt Acquired

No definition available.

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Namespace Prefix:	mdca_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Disposition of Business, Payment Period

+ References

No definition available.

+ Details

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Namespace Prefix:	mdca_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Lessee, Operating Lease, Lease Not yet Commenced, Liability

+ References

No definition available.

+ Details

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Namespace Prefix:	mdca_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Long-term Debt, Accrued Interest

+ References

No definition available.

+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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+ Details

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

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

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Balance Type:	credit
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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

- 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

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Balance Type:	debit
Period Type:	duration

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- Details

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Period Type:

- Details

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- Details

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Basis of Presentation and Recent Developments Basis of Presentation and Recent Developments (Details) - USD ($)		1 Months Ended
	Feb. 14, 2020	Apr. 30, 2020	Feb. 27, 2020	Dec. 31, 2019	Jun. 30, 2019	Mar. 23, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Leases not yet commenced, liability				$ 13,900,000	$ 124,233,000,000
Senior Notes \| 6.50% Notes due 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Debt Instrument, Face Amount						$ 900,000,000
Subsequent Event
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Leases not yet commenced, liability			$ 115,000,000
Subsequent Event \| Senior Notes \| 6.50% Notes due 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed		74.00%
Gain (Loss) on Extinguishment of Debt		$ 8,000,000
Long-term Debt, Accrued Interest		946,000
Debt Acquired		30,000,000
Long-term Debt		$ 22,000,000
Subsequent Event \| Sloane and Company LLC
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	$ 26,000,000
Payment period	2 years
Gain on disposition of business	$ 16,000,000