Consolidated Businesses - Reconciliation of Activity Related to Redeemable Noncontrolling Interest (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Reconciliation activity related to the redeemable non controlling interest
Beginning balance	$ 10,346
Cash redemption			$ (42,315)
Ending balance	10,506	$ 10,346
Redeemable Noncontrolling Interest
Reconciliation activity related to the redeemable non controlling interest
Beginning balance	10,346	3,442	3,383
Redeemable noncontrolling interest portion of subsidiary net income/(loss)	(393)	72	(105)
FolioDynamix impairment charge (1)	(812)
Accretion to estimated redemption value	4,704	6,832	164
Cash redemption	(3,339)
Ending balance	$ 10,506	$ 10,346	$ 3,442

Temporary Equity, Result of Impairment

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.

+ Details

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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

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.

+ Details

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Period Type:	duration

- Details

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