Business Operations (Details) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2013 agent subsidiary outlet sqft room	Jun. 30, 2013	Jun. 30, 2012	Feb. 28, 2013 item sqft	Mar. 31, 2002
Business Operations
Area of casino (in square feet)	165,000
Number of retail outlets	4
Number of rooms in AAA Four Diamond hotel	500
Number of seats in sports-themed restaurant				110
Area of leased property (in square feet)				4,100
Number of wholly owned subsidiaries	2
Percentage of the issued and outstanding common stock of Dover Downs, Inc. contributed by DVD					100.00%
Percentage of issued and outstanding common stock distributed to parent stockholders					100.00%
Number of Licensed Agents under Delaware State Lottery Code	3
Number of consecutive years for which annual license has been received from the Harness Racing Commission	44 years
State-wide net proceeds to be retained in lottery	$ 3,750,000
Gaming license fee paid			1,540,000
Table game license fee paid		2,241,000
Estimated table game license fee for next Delaware Lottery fiscal year	$ 1,000,000
Total gaming win | Geographic concentration risk | Maryland patrons
Business operations
Estimated percentage of gaming win attributable to patrons	35.00%
Capital Club member gaming win | Geographic concentration risk | Out of state patrons
Business operations
Estimated percentage of gaming win attributable to patrons	66.00%