Investments - Financial Information for Knight Capital (Detail) (Knight Capital Group, Inc. [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Knight Capital Group, Inc. [Member]
Subsidiary or Equity Method Investee [Line Items]
Total assets	$ 9,778.4
Total liabilities	8,295.9
Total equity	$ 1,482.5

The amount of assets reported by an equity method investment of the entity.

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+ Details

- Definition

Amount of equity, excluding noncontrolling interest, attributable to the equity method investment of the entity.

+ References+ Details

- Definition

The amount of liabilities reported by an equity method investment of the entity.

+ References

+ Details