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Advertising Costs | 12 Months Ended
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Dec. 31, 2020
Advertising Costs |
Advertising Costs | 11. Advertising Costs Advertising costs are charged to expense as incurred. Advertising costs for the years ended December 31, 2020 and 2019 totaled $130,000 and $351,000, respectively.

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- Definition The entire disclosure for reporting the Company's advertising expenses. + References No definition available. + Details
Name: | dwsn_AdvertisingExpenseTextBlock
Namespace Prefix: | dwsn_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

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- References No definition available. + Details
Name: | us-gaap_MarketingAndAdvertisingExpenseAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration