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	Dec. 31, 2013
Fair Value Assets Measured On Recurring Basis Unobservable Input [Line Items]
Seller note	$ 29
Level 3 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input [Line Items]
Seller note	29
Seller Note [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input [Line Items]
Seller note	29
Seller Note [Member] | Level 3 [Member]
Fair Value Assets Measured On Recurring Basis Unobservable Input [Line Items]
Seller note	$ 29