Annual report pursuant to Section 13 and 15(d)

Nature of Business and Significant Accounting Policies (Long-lived assets) (Details)

v2.4.1.9
Nature of Business and Significant Accounting Policies (Long-lived assets) (Details) (USD $)
3 Months Ended 12 Months Ended 3 Months Ended
Dec. 31, 2014
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Dec. 31, 2014
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Dec. 31, 2013
Dec. 31, 2010
Dec. 31, 2009
Dec. 31, 2013
Mar. 31, 2012
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Sep. 30, 2011
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Impaired Long-Lived Assets Held and Used [Line Items]                
Gain (Loss) on Disposition of Business   $ 1,200,000us-gaap_GainLossOnSaleOfBusiness            
Other Asset Impairment Charges   700,000us-gaap_OtherAssetImpairmentCharges            
Asset Impairment Charges 600,000us-gaap_AssetImpairmentCharges 2,086,000us-gaap_AssetImpairmentCharges 0us-gaap_AssetImpairmentCharges          
Net Rentable Area 9,000us-gaap_NetRentableArea 9,000us-gaap_NetRentableArea         6,700us-gaap_NetRentableArea 47,000us-gaap_NetRentableArea
Segment, Discontinued Operations [Member]                
Impaired Long-Lived Assets Held and Used [Line Items]                
Asset Impairment Charges       600,000us-gaap_AssetImpairmentCharges
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_SegmentDiscontinuedOperationsMember
700,000us-gaap_AssetImpairmentCharges
/ us-gaap_StatementBusinessSegmentsAxis
= us-gaap_SegmentDiscontinuedOperationsMember
     
Marketing Services [Member]                
Impaired Long-Lived Assets Held and Used [Line Items]                
Asset Impairment Charges     $ 600,000us-gaap_AssetImpairmentCharges
/ us-gaap_StatementBusinessSegmentsAxis
= pdii_MarketingServicesMember
    $ 100,000us-gaap_AssetImpairmentCharges
/ us-gaap_StatementBusinessSegmentsAxis
= pdii_MarketingServicesMember