Restructuring Charges - Separation and Restructuring Plan Activity (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Sep. 30, 2013
Restructuring Cost and Reserve [Line Items]
Liability balance	$ 13.2
Increase in liability (separation and other charges)	11.0
Reduction in liability (payments and adjustments)	(6.7)
Liability balance	$ 17.5

Amount of cash payment and translation adjustment increasing or decreasing the accrual for a specified type of restructuring cost.

No definition available.

+ Details

Name:	dv_RestructuringReservePaymentsAndAdjustment
Namespace Prefix:	dv_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_RestructuringCostAndReserveLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SAB TOPIC 5.P.4(b))

-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 5

-Section P

-Subsection 3, 4

+ Details

Name:	us-gaap_RestructuringReserve
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Net total Increase or Decrease in the accrual for restructuring costs during the reporting period.

+ References

+ Details

Name:	us-gaap_RestructuringReservePeriodIncreaseDecrease
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration