Consolidated Businesses - Reconciliation of Activity Related to Redeemable Noncontrolling Interest (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Reconciliation activity related to the redeemable non controlling interest
Balance at December 31, 2015	$ 10,506
Balance at March 31, 2016	5,823
Payments to acquired additional interest in subsidiaries	5,400
Impact of subsidiary equity transactions	620	$ 626
Redeemable Noncontrolling Interest
Reconciliation activity related to the redeemable non controlling interest
Balance at December 31, 2015	10,506	6,221
Redeemable noncontrolling interest portion of subsidiary net loss	(69)	(68)
Accretion to estimated redemption value	633	1,303
Equity transfer among owners	(5,247)	(3,339)
Impact of subsidiary equity transactions		(631)
Balance at March 31, 2016	5,823	$ 3,486
GovDelivery
Reconciliation activity related to the redeemable non controlling interest
Payments to acquired additional interest in subsidiaries	$ 2,500
Ownership percentage by parent	94.00%		92.00%
VelocityEHS
Reconciliation activity related to the redeemable non controlling interest
Payments to acquired additional interest in subsidiaries	$ 2,400
Ownership percentage by parent	99.00%		98.00%
FolioDynamix
Reconciliation activity related to the redeemable non controlling interest
Payments to acquired additional interest in subsidiaries	$ 500

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

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

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- Definition

The cash outflow associated with the purchase of noncontrolling interest during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585

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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

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- Definition

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

+ References

No definition available.

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- Definition

Amount of increase (decrease) in temporary equity from changes classified as other.

+ References

No definition available.

+ Details

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