Cash and Cash Equivalents (Cash and Cash Equivalents) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Cash and Cash Equivalents [Line Items]
Cash and due from banks	$ 19,408	$ 82,273
Interest bearing deposits in banks	1,818	1,479
FHLB [Member]
Cash and Cash Equivalents [Line Items]
Interest bearing deposits in banks	$ 803	464
Interest Rate	1.57%
M&T Fed Funds sold [Member]
Cash and Cash Equivalents [Line Items]
Interest bearing deposits in banks	$ 1,015	$ 1,015
Interest Rate	0.15%
Weighted Average [Member]
Cash and Cash Equivalents [Line Items]
Interest Rate	1.05%

Percentage of interest income earned on a cash and cash equivalents account.

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.

+ Details

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- Definition

For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

+ References

+ Details

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- Definition

For banks and other depository institutions (including Federal Reserve Banks, if applicable): Interest-bearing deposits in other financial institutions for relatively short periods of time including, for example, certificates of deposits, which are presented separately from cash on the balance sheet.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.2)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=73530178&loc=d3e59706-112781

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- Details

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- Details

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