Capital (Mandatorily Redeemable Capital Stock) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Mandatorily Redeemable Capital Stock [Roll Forward]
Balance at beginning period	$ 34,782
Net Shares Reclassified to Mandatorily Redeemable Capital Stock, Value	187,405	$ 237,883
Repayments of Mandatory Redeemable Capital Securities	(186,218)	$ (179,929)
Balance at end of period	$ 35,969

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Value of net shares reclassified to mandatorily redeemable capital stock.

+ References

No definition available.

+ Details

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- Definition

The cash outflow related to equity securities that embody an unconditional obligation requiring the issuer to redeem the securities by transferring the assets at a specified or determinable date (or dates) that is (or are) initially more than one year (or the normal operating cycle, if longer) from the issuance date, or upon an event that is certain to occur beyond one year (or the normal operating cycle, if longer) from the issuance date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

+ Details

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- Definition

Amount that would be paid, determined under the conditions specified in the contract, if the holder of the share has the right to redeem the shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6940734&loc=d3e22047-110879

+ Details

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