Investments (Pledged Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Compliance With Reinsurance Contract Provisions Or Insurance Laws [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Restricted cash, cash equivalents and investments	$ 2,975,115	$ 3,585,792
Pledged As Collateral For Letter Of Credit Facilities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Restricted cash, cash equivalents and investments	$ 570,363	$ 571,750

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.

No definition available.

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