Goodwill and Intangibles, including DAC and VOBA - Summary of Changes in Carrying Amounts of Goodwill and Intangible Assets Including FGL's DAC and VOBA Balances (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended		15 Months Ended
	Jun. 30, 2013	Jun. 30, 2013	Jul. 01, 2012	Jul. 01, 2013
Intangible Assets, Including Goodwill [Roll Forward]
Beginning Balance, Goodwill		$ 694.2
Beginning Balance, Indefinite Lived Intangible Assets		841.1
Beginning Balance, Finite Lived Intangible Assets		873.9
Beginning Balance, Intangible Assets, Excluding Goodwill		1,988.5
Acquisitions (Note 3), Goodwill		787.7
Acquisitions (Note 3), Indefinite Lived Intangible Assets		330.0
Acquisitions (Note 13)		520.6
Deferrals		109.2
Less: Components of amortization:
Amortization of intangibles	85.0	220.6	158.5	43.0
Adjustment for unrealized investment (gains), net, Goodwill		260.9
Effect of translation, Goodwill		(11.7)
Effect of translation, Indefinite Lived intangible assets		(4.2)
Effect of translation, Intangible Assets Excluding Goodwill		(8.7)
Ending Balance, Goodwill	1,470.2	1,470.2
Ending Balance, Indefinite Lived Intangible Assets	1,166.9	1,166.9
Ending Balance, Finite Lived Intangible Assets	1,002.5	1,002.5
Ending Balance, Intangible Assets, Excluding Goodwill	2,649.9	2,649.9
Unlocking [Member]
Less: Components of amortization:
Goodwill Amortization
Indefinite Lived Intangible Assets, Amortization
Amortization of intangibles		(27.4)
Reclassifications [Member]
Less: Components of amortization:
Goodwill Amortization
Indefinite Lived Intangible Assets, Amortization
Amortization of intangibles
Interest [Member]
Less: Components of amortization:
Goodwill Amortization
Indefinite Lived Intangible Assets, Amortization
Amortization of intangibles		(23.3)
Periodic amortization [Member]
Less: Components of amortization:
Goodwill Amortization
Indefinite Lived Intangible Assets, Amortization
Amortization of intangibles		271.3
Definite Lived Intangible Assets [Member]
Intangible Assets, Including Goodwill [Roll Forward]
Beginning Balance, Finite Lived Intangible Assets		873.9
Acquisitions (Note 3), Finite-Lived Intangible Assets		190.6
Deferrals
Less: Components of amortization:
Amortization of intangibles	20.3	57.5	46.5	16.1
Adjustment for unrealized investment (gains), net, Goodwill
Effect of translation, Finite Lived intangible assets		(4.5)
Ending Balance, Finite Lived Intangible Assets	1,002.5	1,002.5
Definite Lived Intangible Assets [Member] | Unlocking [Member]
Less: Components of amortization:
Amortization of intangibles
Definite Lived Intangible Assets [Member] | Reclassifications [Member]
Less: Components of amortization:
Amortization of intangibles
Definite Lived Intangible Assets [Member] | Interest [Member]
Less: Components of amortization:
Amortization of intangibles
Definite Lived Intangible Assets [Member] | Periodic amortization [Member]
Less: Components of amortization:
Amortization of intangibles		57.5
VOBA [Member]
Intangible Assets, Including Goodwill [Roll Forward]
Beginning Balance, Finite Lived Intangible Assets		104.3
Acquisitions (Note 3), Finite-Lived Intangible Assets
Deferrals
Less: Components of amortization:
Amortization of intangibles	37.3	113.0	101.3	23.8
Adjustment for unrealized investment (gains), net, Goodwill		211.3
Effect of translation, Finite Lived intangible assets
Ending Balance, Finite Lived Intangible Assets	202.6	202.6
VOBA [Member] | Unlocking [Member]
Less: Components of amortization:
Amortization of intangibles		(22.6)
VOBA [Member] | Reclassifications [Member]
Less: Components of amortization:
Amortization of intangibles
VOBA [Member] | Interest [Member]
Less: Components of amortization:
Amortization of intangibles		(16.2)
VOBA [Member] | Periodic amortization [Member]
Less: Components of amortization:
Amortization of intangibles		151.8
DAC [Member]
Intangible Assets, Including Goodwill [Roll Forward]
Beginning Balance, Finite Lived Intangible Assets		169.2
Acquisitions (Note 3), Finite-Lived Intangible Assets
Deferrals		109.2
Less: Components of amortization:
Amortization of intangibles	27.4	50.1	10.7	3.1
Adjustment for unrealized investment (gains), net, Goodwill		49.6
Effect of translation, Finite Lived intangible assets
Ending Balance, Finite Lived Intangible Assets	277.9	277.9
DAC [Member] | Unlocking [Member]
Less: Components of amortization:
Amortization of intangibles		(4.8)
DAC [Member] | Reclassifications [Member]
Less: Components of amortization:
Amortization of intangibles
DAC [Member] | Interest [Member]
Less: Components of amortization:
Amortization of intangibles		(7.1)
DAC [Member] | Periodic amortization [Member]
Less: Components of amortization:
Amortization of intangibles		62.0
Goodwill [Member]
Intangible Assets, Including Goodwill [Roll Forward]
Deferrals
Less: Components of amortization:
Adjustment for unrealized investment (gains), net, Goodwill
Indefinite Lived Intangible Assets [Member]
Intangible Assets, Including Goodwill [Roll Forward]
Deferrals
Less: Components of amortization:
Adjustment for unrealized investment (gains), net, Goodwill