- Definition

Number of lawsuits alleging Transatlantic Holdings, Inc. aided and abetted its directors' alleged breach of a fiduciary duty.

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- Definition

Number of New York lawsuits moved to consolidate into one lawsuit.

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- Definition

Number of lawsuits naming a former director of Transatlantic Holdings, Inc. as a defendant.

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- Definition

The number of New York lawsuits that defendants moved to dismiss or stay.

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- Definition

The number of Delaware lawsuits consolidating into one lawsuit.

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- Definition

Number of lawsuits filed that also name GO Sub LLC as a defendant.

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- Definition

Number of lawsuits filed related to the merger resulting from the merger agreement between Transatlantic Holdings, Inc., Allied World Assurance Company Holdings AG and GO Sub LLC dated June 12, 2011.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Legal Proceedings (Details 2) (Stockholder Class Action Lawsuits)	6 Months Ended
	Jun. 30, 2011	Jul. 25, 2011	Jul. 21, 2011	Jun. 29, 2011
Stockholder Class Action Lawsuits
Legal Proceedings
Lawsuits filed in connection with the merger	5
Lawsuits also naming GO Sub LLC as a defendant	4
Claims moved to dismiss or stay				3
Lawsuits consolidated into one lawsuit, Number			2
Lawsuits naming a former director of Transatlantic Holdings, Inc.	1
Lawsuits alleging aiding and abetting breach of fiduciary duty	1
Lawsuits moved to consolidate in New York		3