Investments (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Trading
Short-term investments	$ 13,160us-gaap_TradingSecurities	$ 37,405us-gaap_TradingSecurities
Available-for-sale
Securitized assets	5,938us-gaap_AvailableForSaleSecurities	3,721us-gaap_AvailableForSaleSecurities
Held-to-maturity
Securitized assets	53,716us-gaap_HeldToMaturitySecurities	31,017us-gaap_HeldToMaturitySecurities
Other investments
Private equity funds	18,656us-gaap_OtherInvestments	17,560us-gaap_OtherInvestments
Investments	$ 91,470us-gaap_Investments	$ 89,703us-gaap_Investments

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

+ References

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Sum of the carrying amounts as of the balance sheet date of all investments.

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Other investments not otherwise specified in the taxonomy.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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-Glossary Trading Securities

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