Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2011

Accounting Policies [Abstract]

Previously Reported Third-Party Distribution, Service And Advisory And Marketing Expenses

	For the year ended December 31,
$ in millions	2010		2009
Third-party distribution, service and advisory expenses, as previously reported	972.7		693.4
Reclassification	81.1		43.6
Third-party distribution, service and advisory expenses, as reclassified	1,053.8		737.0
Marketing expenses, as previously reported	159.6		108.9
Reclassification	(81.1	)	(43.6	)
Marketing expenses, as reclassified	78.5		65.3