Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Equity investments, at estimated fair value, pledged as collateral (in dollars)	$ 86,047	$ 61,543
Preferred shares, no par value (in dollars per share)
Preferred shares, shares authorized	50,000,000us-gaap_PreferredStockSharesAuthorized	50,000,000us-gaap_PreferredStockSharesAuthorized
Preferred shares, shares issued	14,950,000us-gaap_PreferredStockSharesIssued	14,950,000us-gaap_PreferredStockSharesIssued
Preferred shares, shares outstanding	14,950,000us-gaap_PreferredStockSharesOutstanding	14,950,000us-gaap_PreferredStockSharesOutstanding
Common shares, no par value (in dollars per share)
Common shares, shares authorized	500,000,000us-gaap_CommonStockSharesAuthorized	500,000,000us-gaap_CommonStockSharesAuthorized
Common shares, shares issued	100us-gaap_CommonStockSharesIssued	100us-gaap_CommonStockSharesIssued
Common shares, shares outstanding	100us-gaap_CommonStockSharesOutstanding	100us-gaap_CommonStockSharesOutstanding

Face amount per share of no-par value common stock.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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The fair value as of the balance sheet date of financial instruments and other positions owned by the entity and pledged to counterparties as collateral, including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities.

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Face amount per share of no-par value preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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