Reconciliation of Activity Related to Redeemable Noncontrolling Interest (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Reconciliation activity related to the redeemable non controlling interest
Beginning Balance	$ 3,442
Accretion to estimated redemption value	2,774	1,088	839
Impact of subsidiary equity transactions	4,241	(5,799)	64,014
Ending Balance	6,221	3,442
Redeemable Noncontrolling Interest
Reconciliation activity related to the redeemable non controlling interest
Beginning Balance	3,442	3,383	1,378
Redeemable noncontrolling interest portion of subsidiary net loss	72	(105)	(149)
Accretion to estimated redemption value	3,095	1,088	839
Acquisition of MSDSonline			1,309
Impact of subsidiary equity transactions	(388)	(924)	6
Ending Balance	$ 6,221	$ 3,442	$ 3,383

Other activity regarding equity transfers among controlling entity (ACTUA) and noncontrolling owners.

No definition available.

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- Details

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- Definition

Value of accretion of temporary equity to its redemption value during the period.

+ References

No definition available.

+ Details

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- Definition

Carrying amount, attributable to parent and noncontrolling interests, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.27(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

The portion of net income or loss attributable to temporary equity interest.

+ References

No definition available.

+ Details

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- Definition

Value of new stock classified as temporary equity issued during the period.

+ References

No definition available.

+ Details

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