Condensed Consolidated Balance Sheets (Parenthetical) In Thousands, except Share data	Sep. 30, 2011 USD ($)	Sep. 30, 2011 CHF	Dec. 31, 2010 USD ($)	Dec. 31, 2010 CHF
Condensed Consolidated Balance Sheets [Abstract]
Amortized cost of fixed maturity investments available for sale, at fair value	$ 264,050		$ 828,544
Common shares, par value		14.38		15.00
Common shares, issued	40,003,642	40,003,642	40,003,642	40,003,642
Common shares, outstanding	38,145,557	38,145,557	38,089,226	38,089,226
Treasury stock, shares	1,858,085	1,858,085	1,914,416	1,914,416

This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are classified neither as held-to-maturity nor trading securities.

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Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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