Summary of Investments - SOI Ltd partnership Sec lending Special deposits (Details 5) - USD ($)	Jun. 30, 2017	Dec. 31, 2016
Investments, Debt and Equity Securities [Abstract]
Limited partnership and other corporation interests	$ 37,876,000	$ 34,895,000
Nature and activities of the VIEs and the effect on financial statements
Carrying value in relation to the activities of the VIEs	35,492,000	32,444,000
Maximum exposure to loss in relation to the activities of the VIEs	35,565,000	32,444,000
Special deposits and securities lending
Amortized cost	124,185,000
Securities loaned to third parties at fair value	121,582,000	0
Collateral received	77,614,000	$ 0
Collateral fair value	$ 48,214,000

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Total investments in (A) an entity in which the entity has significant influence, but does not have control, (B) subsidiaries that are not required to be consolidated and are accounted for using the equity and or cost method, and (C) an entity in which the reporting entity shares control of the entity with another party or group. Includes long-term advances receivable from a party that is affiliated with the reporting entity by means of direct or indirect ownership.

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Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value of the securities pledged as collateral against securities loaned.

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The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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