Amount of required monthly rental payments for operating leases.

No definition available.

Name:	dmlp_OperatingLeasesFutureMonthlyPayments
Namespace Prefix:	dmlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

A tenant improvement allowance associated with an operating lease.

+ References

No definition available.

+ Details

Name:	dmlp_TenantImprovementAllowance
Namespace Prefix:	dmlp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

+ Details

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

- Definition

Term of the lessee's leasing arrangement renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LesseeLeasingArrangementsOperatingLeasesRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Term of the lessee's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_LesseeLeasingArrangementsOperatingLeasesTermOfContract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Note 4 - Commitments and Contingencies (Details Textual) - USD ($)		12 Months Ended
	Feb. 17, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Lessee Leasing Arrangements, Operating Leases, Term of Contract	2 years 30 days
Lessee Leasing Arrangements, Operating Leases, Renewal Term	1 year
Tenant Improvement Allowance	$ 113,000
Operating Leases, Rent Expense		$ 272,000	$ 231,000	$ 268,000
Minimum [Member]
Operating Leases, Future Monthly Payments	26,000
Maximum [Member]
Operating Leases, Future Monthly Payments	$ 27,000