Advances (Year of Contractual Maturity or Next Call Date) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Advances [Abstract]
Federal Home Loan Bank Advances, Earlier of Contractual Maturity or Next Call Date, Due With in Next Rolling Twelve Months	$ 41,825,393	$ 33,831,156
Federal Home Loan Bank Advances Earlier of Contractual Maturity or Next Call Date Due in Rolling Year Two	16,949,195	15,901,805
Federal Home Loan Bank Advances Earlier of Contractual Maturity or Next Call Date Due in Rolling Year Three	7,612,968	13,608,214
Federal Home Loan Bank Advances Earlier of Contractual Maturity or Next Call Date Due in Rolling Year Four	2,831,913	2,982,425
Federal Home Loan Bank Advances Earlier of Contractual Maturity or Next Call Date Due in Rolling Year Five	592,255	2,243,105
Federal Home Loan Bank Advances Earlier of Contractual Maturity or Next Call Date Due After Rolling Year Five	1,300,756	1,340,316
Federal Home Loan Bank, Advances, Par Value, Total	$ 71,112,480	$ 69,907,021

Advances [Abstract]

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- Definition

Par amount of advances made and reported by Federal Home Loan Bank (FHLBank) with the earlier of contractual maturity or next call date after the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Par amount of advances made and reported by Federal Home Loan Bank (FHLBank) with the earlier of contractual maturity or next call date within the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Par amount of advances made and reported by Federal Home Loan Bank (FHLBank) with the earlier of contractual maturity or next call date within the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Par amount of advances made and reported by Federal Home Loan Bank (FHLBank) with the earlier of contractual maturity or next call date within the fourth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Par amount of advances made and reported by Federal Home Loan Bank (FHLBank) with the earlier of contractual maturity or next call date within the third rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

+ Details

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- Definition

Par amount of advances made and reported by Federal Home Loan Bank (FHLBank) with the earlier of contractual maturity or next call date within the second rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Par amount of advances made and reported by Federal Home Loan Bank (FHLBank).

+ References

No definition available.

+ Details

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