Debt Obligations - Repurchase Obligations Outstanding (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013 SecurityLoan
Debt Disclosure [Abstract]
Number of loans not pledged under repurchase agreements	2
Aggregate principal balance	$ 173.8

Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5086-111524

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 50

-Paragraph 1A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7523297&loc=SL6224234-111729

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