Investment securities.

No definition available.

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- Definition

Taxable Equivalent Yield is the return that is required on a taxable investment to make it equal to the return on a tax-exempt investment.

+ References

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.

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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.

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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

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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

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- Definition

The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26853-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a),(b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

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- Definition

The carrying value as of the balance sheet date of the assets received as collateral against securities loaned to other broker-dealers. Borrowers of securities generally are required to provide collateral to the lenders of securities, commonly cash but sometimes other securities or standby letters of credit, with a value slightly higher than that of the securities borrowed. In instances where the entity is permitted to sell or re-pledge these securities, the entity reports the fair value of the collateral received and the related obligation to return the collateral as a liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 10
-Section 05
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=109246787&loc=d3e93645-111703

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Investment Securities (Details Textual) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended	9 Months Ended
	Feb. 01, 2018	Sep. 30, 2018	Jun. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Investment Securities (Textuals) [Abstract]
Proceeds from Sale of Available-for-sale Securities		$ 108,000		$ 601,130	$ 0
Debt Securities, Held-to-maturity, Sold, Amount					$ 16,000
Federal Home Loan Bank Stock		144,000		144,000		$ 89,000
Federal Reserve Bank Stock		77,000		77,000		76,000
Bank Mutual
Business Acquisition [Line Items]
Debt Securities, Available-for-sale, Sold at Par Value	$ 453,000
Investment Securities (Textuals) [Abstract]
Debt Securities, Available-for-sale, Sold at Par Value	$ 453,000
Investment Securities Class
Investment Securities (Textuals) [Abstract]
Securities Received as Collateral		$ 3,700,000		$ 3,700,000		$ 3,100,000
Securities Sold
Business Acquisition [Line Items]
Taxable Equivalent Yield		3.08%
Reinvestment
Business Acquisition [Line Items]
Taxable Equivalent Yield		3.51%
GNMA Commercial Mortgage-Related Securities
Business Acquisition [Line Items]
Debt Securities, Available-for-sale, Sold at Par Value			$ 40,000
Investment Securities (Textuals) [Abstract]
Debt Securities, Available-for-sale, Sold at Par Value			$ 40,000