Securities Lending - Gross and Net Securities Borrowing and Lending Balances (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Brokers And Dealers [Abstract]
Gross amounts recognized	$ 685,037	$ 594,674
Gross amounts offset in the consolidated balance sheets	0	0
Net amounts included in the consolidated balance sheets	685,037	594,674
Amounts not offset in the balance sheet but eligible for offsetting upon counterparty default	685,037	594,674
Net amounts	0	0
Gross amounts recognized	687,443	595,717
Gross amounts offset in the consolidated balance sheets	0	0
Net amounts included in the consolidated balance sheets	687,443	595,717
Amounts not offset in the balance sheet but eligible for offsetting upon counterparty default	687,443	595,717
Net amounts	$ 0	$ 0

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount, before effects of master netting arrangements, of securities borrowed from entities in exchange for collateral. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of liability associated with securities borrowed from entities in exchange for collateral.

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Amount of securities borrowed from entities in exchange for collateral, elected not to be offset, deducted from securities borrowed.

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Amount, after effects of master netting arrangements, deduction of assets not subject to a master netting arrangement and elected not to be offset, of securities borrowed from entities in exchange for collateral, offset against an obligation to return collateral under a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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