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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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Namespace Prefix:	dble_
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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 Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

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

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Compensation Plans (Details Textual) (USD $)	3 Months Ended		9 Months Ended
Compensation Plans (Details Textual) (USD $)	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Compensation Plans (Additional Textual) [Abstract]
Stock-based compensation expense	$ 54,000	$ 414,000	$ 570,000	$ 1,234,000
Compensation Plans (Textual) [Abstract]
Nonvested shares of common stock outstanding	459,001		459,001		533,981
LTIP
Compensation Plans (Additional Textual) [Abstract]
Stock-based compensation expense	(16,000)	164,000	218,000	468,000
Compensation Plans (Textual) [Abstract]
Nonvested shares of common stock outstanding	405,262		405,262
Expenses related to long term incentive plan			$ 2,700,000
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%