Investment securities.

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with interest rate reset through auction process, sold at par value.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt security, measured at amortized cost, sold.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27405-111563

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809

+ Details

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- Definition

Federal Reserve Bank stock represents an equity interest in the Federal Reserve Bank. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

+ Details

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Investment Securities (Details Textual) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Business Acquisition [Line Items]
Debt Securities, Available-for-sale, Sold at Par Value	$ 40
Investment Securities (Textuals) [Abstract]
Debt Securities, Available-for-sale, Sold at Par Value	40
Debt Securities, Held-to-maturity, Sold, Amount		$ 16
Federal Home Loan Bank Stock	173		$ 89
Federal Reserve Bank Stock	76		$ 76
Bank Mutual [Member]
Business Acquisition [Line Items]
Debt Securities, Available-for-sale, Sold at Par Value	453
Investment Securities (Textuals) [Abstract]
Debt Securities, Available-for-sale, Sold at Par Value	$ 453