Quarterly Dividend - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended
Feb. 03, 2014	Dec. 31, 2014
Dividends Payable [Line Items]
Dividend payable per share	$ 0.08us-gaap_DividendsPayableAmountPerShare
Dividend declared date	Feb. 03, 2014
Quarterly dividend paid amount	$ 645,000dwsn_QuarterlyDividendCash
Dividend paid amount on annualized basis	$ 2,580,000us-gaap_DividendsCash
Period One
Dividends Payable [Line Items]
Dividend paid date		Feb. 24, 2014
Dividend record date		Feb. 14, 2014
Period Two
Dividends Payable [Line Items]
Dividend paid date		May 30, 2014
Dividend record date		May 16, 2014
Period Three
Dividends Payable [Line Items]
Dividend paid date		Aug. 29, 2014
Dividend record date		Aug. 15, 2014
Period Four
Dividends Payable [Line Items]
Dividend paid date		Dec. 08, 2014
Dividend record date		Nov. 24, 2014

Quarterly dividend cash.

No definition available.

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Namespace Prefix:	dwsn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

+ Details

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Period Type:	duration

- Definition

Amount of paid and unpaid cash dividends declared for classes of stock, for example, but not limited to, common and preferred.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 405

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

+ Details

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

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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