Geographic Information (Tables)

12 Months Ended

Dec. 31, 2012

Segments, Geographical Areas [Abstract]

Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas

The company operates under one business segment, investment management. Geographical information is presented below. There are no revenues or long-lived assets attributed to the company's country of domicile, Bermuda.

$ in millions	U.S.		U.K./Ireland		Canada		Continental Europe	Asia	Total
For the year ended December 31, 2012
Revenue from external customers	2,190.2		1,492.1		346.4		43.0	105.3	4,177.0
Inter-company revenue	(6.5	)	(144.0	)	(13.2	)	78.3	85.4	—
Total operating revenues	2,183.7		1,348.1		333.2		121.3	190.7	4,177.0
Long-lived assets	228.7		83.6		9.4		7.1	20.8	349.6
For the year ended December 31, 2011
Revenue from external customers	2,090.2		1,473.1		372.3		38.8	117.8	4,092.2
Inter-company revenue	(8.1	)	(152.8	)	(14.1	)	76.7	98.3	—
Total operating revenues	2,082.1		1,320.3		358.2		115.5	216.1	4,092.2
Long-lived assets	196.7		81.5		7.9		4.9	21.8	312.8
For the year ended December 31, 2010
Revenue from external customers	1,680.8		1,305.8		370.7		44.3	86.1	3,487.7
Inter-company revenue	9.8		(131.3	)	(10.1	)	56.3	75.3	—
Total operating revenues	1,690.6		1,174.5		360.6		100.6	161.4	3,487.7
Long-lived assets	169.3		79.6		7.6		2.8	13.1	272.4