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- Definition

Maximum amount of share based compensation expense that would be recognized under long-term incentive plan.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage portion of shares employee may earn by continued employment with company.

+ References

No definition available.

+ Details

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- Definition

Percentage remaining portion of shares employee may earn through increase in net assets value.

+ References

No definition available.

+ Details

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Namespace Prefix:	dble_
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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Balance Type:	na
Period Type:	instant

Compensation Plans (Details Textual) (USD $)	3 Months Ended
Compensation Plans (Details Textual) (USD $)	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2011
Compensation Plans (Additional Textual) [Abstract]
Stock-based compensation expense	$ 282,000	$ 414,000
LTIP
Compensation Plans (Additional Textual) [Abstract]
Stock-based compensation expense	117,000	140,000
Compensation Plans (Textual) [Abstract]
Aggregate share of common stock			476,906
Expenses related to long term incentive plan	$ 3,100,000
Percentage portion of shares employee may earn by continued employment with company	33.30%
Percentage remaining portion of shares employee may earn through increase in net asset value	66.70%