Condensed Consolidated Statement Of Stockholders' Equity (Parenthetical) (USD $)	3 Months Ended
Mar. 31, 2015
Statement of Stockholders' Equity [Abstract]
Issuance of common stock (in shares)	283,724
Issuance Of Deferred Stock Units Shares	36,579dw_IssuanceOfDeferredStockUnitsShares
Special cash dividend (in usd per share)	$ 2.00

Number of share options (or share units) exercised during the current period.

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

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