Acquisitions and Discontinued Operations -Victory Seller Note Measured at Fair Value on Recurring Basis (Detail) (Victory Capital Management [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2013
Fair Value Assets Measured On Recurring Basis Unobservable Inputs [Line Items]
Seller note	$ 31
Level 1 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Inputs [Line Items]
Seller note
Level 2 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Inputs [Line Items]
Seller note
Level 3 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Inputs [Line Items]
Seller note	31
Seller Note [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Inputs [Line Items]
Seller note	31
Seller Note [Member] | Level 1 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Inputs [Line Items]
Seller note
Seller Note [Member] | Level 2 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Inputs [Line Items]
Seller note
Seller Note [Member] | Level 3 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Inputs [Line Items]
Seller note	$ 31