Business Operations (Details)	6 Months Ended
Jun. 30, 2016 ft² room item	Dec. 31, 2014 item
Business Operations
Area of casino (in square feet) \| ft²	165,000
Number of retail outlets	4
Number of rooms in AAA Four Diamond hotel \| room	500
Number of Licensed Agents under Delaware State Lottery Code	3	3
Number of consecutive years for which annual license has been received from the Harness Racing Commission	47 years
Gaming win \| Geographic concentration risk \| Maryland patrons
Risks and Uncertainties
Estimated percentage of gaming win attributable to patrons	30.00%
Capital Club member gaming win \| Geographic concentration risk \| Out of state patrons
Risks and Uncertainties
Estimated percentage of gaming win attributable to patrons	62.00%

Represents the area of the casino.

No definition available.

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Namespace Prefix:	dde_
Data Type:	num:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Disclosure related to the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. Also information about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward.

+ References

No definition available.

+ Details

Name:	dde_BusinessOperationsAbstract
Namespace Prefix:	dde_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of licensed agents under the Delaware State Lottery Code.

+ References

No definition available.

+ Details

Name:	dde_LicensedAgentsNumberUnderDelawareStateLotteryCode
Namespace Prefix:	dde_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the number of consecutive years for which annual license has been received from the Delaware Harness Racing Commission.

+ References

No definition available.

+ Details

Name:	dde_NumberOfConsecutiveYearsForWhichAnnualLicenseHasBeenReceived
Namespace Prefix:	dde_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the number of retail outlets.

+ References

No definition available.

+ Details

Name:	dde_NumberOfRetailOutlets
Namespace Prefix:	dde_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the number of rooms in the hotel operated by the entity.

+ References

No definition available.

+ Details

Name:	dde_NumberOfRoomsInHotel
Namespace Prefix:	dde_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611

+ Details

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

- References

No definition available.

+ Details

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

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=dde_GamingSalesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=us-gaap_GeographicConcentrationRiskMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=stpr_MD
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=dde_SalesFromCapitalClubMemberGamingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementGeographicalAxis=dde_OutOfStateMember
Namespace Prefix:
Data Type:	na
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Period Type: