Schedule III - Supplementary Insurance Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2012	Sep. 30, 2011
Supplementary Insurance Information, by Segment [Line Items]
Deferred acquisition costs	$ 169,223	$ 38,107
Future policy benefits, losses, claims and loss expenses	3,614,788	3,598,208
Unearned premiums
Other policy claims and benefits payable	91,082	56,650
Premium revenue	55,297	39,002
Net investment income	716,176	369,840
Benefits, claims, losses and settlement expenses	(777,372)	(247,632)
Amortization of deferred acquisition costs	(15,219)	(899)
Other operating expenses	$ (119,913)	$ (72,390)

Amount of amortization of deferred policy acquisition costs recognized.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 16

-Article 12

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 235

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-16)

-URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574960-122915

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Amount of insurance benefits, claims, losses and settlement expenses incurred.

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Net amount of deferred policy acquisition costs capitalized on contracts remaining in force on the balance sheet date.

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Amount of reserves for future policy claims payable and loss expenses to be incurred.

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Amount of net investment income earned.

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Amount of other operating expense incurred.

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Amount of claims and benefits payable not included within other categories.

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Amount of premium revenue earned.

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Amount of premiums not yet earned.

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