v3.3.0.814

Reverse Repurchase and Repurchase Agreements - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Dec. 31, 2014
Securities Financing Transaction [Line Items]
U.S. and non-U.S. government and agency securities, asset-backed securities and corporate debt	$ 84.8
Securities repledged, delivered or used to settle Securities Sold, Not Yet Purchased	84.8
Pledged securities with carrying value to collateralize its repurchase agreements	$ 65.5	$ 44.8

X

- Definition

The carrying value as of the balance sheet date of securities received as collateral from a counterparty that were re-pledged, sold, delivered or otherwise reused by the entity.

+ References

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 860



-SubTopic 30



-Section 50



-Paragraph 1A



-Subparagraph (c)(2)



-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL6224234-111729

+ Details

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

X

- Definition

Fair value of the collateral, or portion thereof, that has been re-pledged, delivered, or otherwise used.

+ References

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 860



-SubTopic 30



-Section 50



-Paragraph 1A



-Subparagraph (c)(2)



-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL6224234-111729

+ Details

Name:	us-gaap_FairValueOfSecuritiesReceivedAsCollateralThatHaveBeenResoldOrRepledged
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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

X

- Definition

The fair value of collateral received that has been sold or re-pledged and is owed to the debtor (transferor) upon settlement of the related contractual obligation under which it was received.

+ References

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 860



-SubTopic 30



-Section 50



-Paragraph 1A



-Subparagraph (c)(2)



-URI http://asc.fasb.org/extlink&oid=55761124&loc=SL6224234-111729

+ Details

Name:	us-gaap_SecuritiesReceivedAsCollateralAmountRepledgedAndSold
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration