Debt Acquired

No definition available.

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

- Definition

The percentage of the face amount of the debt instrument applicable to the change in ownership.

+ References

No definition available.

+ Details

Name:	mdca_DebtInstrumentPercentageOfRedemptionPriceChangeInOwnershipControl
Namespace Prefix:	mdca_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Debt instrument, percentage of redemption price, redemption date, latest for redemption at face amount

+ References

No definition available.

+ Details

Name:	mdca_DebtInstrumentPercentageOfRedemptionPriceRedemptionDateLatestForRedemptionAtFaceAmount
Namespace Prefix:	mdca_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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

- Definition

Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

+ Details

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

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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-Publisher FASB
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
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-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
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-Subparagraph (SX 210.9-03.16)
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+ Details

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

- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=us-gaap_RevolvingCreditFacilityMember
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
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- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
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Balance Type:
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- Details

Name:	us-gaap_DebtInstrumentAxis=mdca_AmendmentCreditAgreementMember
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- Details

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- Details

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- Details

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Debt (Details Textual)		1 Months Ended	12 Months Ended
Debt (Details Textual)	Mar. 23, 2016 USD ($)	Apr. 30, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2020	Mar. 31, 2020 USD ($)	Mar. 31, 2019	Mar. 12, 2019 USD ($)	May 03, 2016 USD ($)
Debt [Line Items]
Interest Expense, Debt			$ 62,210,000	$ 64,420,000	$ 62,001,000
Amortization of Debt Issuance Costs and Discounts			3,346,000	3,193,000	$ 3,022,000
Amount of letters of credit outstanding			4,836,000	4,701,000			$ 17,576,000
6.50% Notes due 2024
Debt [Line Items]
Senior Notes	$ 900,000,000		$ 900,000,000	$ 900,000,000			$ 900,000,000
Wells Fargo Capital Finance, LLC \| Revolving Credit Facility [Member]
Debt [Line Items]
Maximum borrowing capacity										$ 325,000,000
Ratio of Indebtedness to Net Capital										5.5
Senior Notes \| 6.50% Notes due 2024
Debt [Line Items]
Debt Instrument, Face Amount	$ 900,000,000
Interest rate, stated percentage	6.50%		6.50%					6.50%
Debt Instrument, Percentage Of Redemption Price, Change In Ownership Control	101.00%		101.00%
Debt Instrument, Percentage Of Redemption Price, Redemption Date, Latest For Redemption At Face Amount	100.00%		100.00%
Debt instrument, maturity date	May 01, 2024
Line of Credit [Member] \| Amendment, Credit Agreement [Member]
Debt [Line Items]
Maximum borrowing capacity			$ 250,000,000						$ 250,000,000
Ratio of Indebtedness to Net Capital									6.25
Forecast \| Line of Credit [Member] \| Amendment, Credit Agreement [Member]
Debt [Line Items]
Ratio of Indebtedness to Net Capital						5.5
Subsequent Event [Member] \| Senior Notes \| 6.50% Notes due 2024
Debt [Line Items]
Debt Acquired		$ 30,000,000
Non-Prime Rate and Prime Rate on European Advances [Member] \| Wells Fargo Capital Finance, LLC
Debt [Line Items]
Interest rate, stated percentage										0.75%
Non-Prime Rate and Prime Rate on European Advances [Member] \| Wells Fargo Capital Finance, LLC \| Revolving Credit Facility [Member]
Debt [Line Items]
Interest rate, stated percentage									0.75%
Base Rate [Member] \| Wells Fargo Capital Finance, LLC
Debt [Line Items]
Interest rate, stated percentage										1.50%
Base Rate [Member] \| Wells Fargo Capital Finance, LLC \| Revolving Credit Facility [Member]
Debt [Line Items]
Interest rate, stated percentage									1.50%