Fair Value Measurements (Estimated Fair Values of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financial assets:
Cash and cash equivalents	$ 58,398	$ 42,832
Securities	809,081	847,961
Loans held for sale	5,628	5,037
Loans, net	1,985,025	1,980,846
Restricted investments in bank stock	16,021	15,223
Accrued interest receivable	7,644	7,349
Financial liabilities:
Deposits	2,413,948us-gaap_DepositsFairValueDisclosure	2,383,085us-gaap_DepositsFairValueDisclosure
Short-term borrowings	246,986	333,475
Long-term debt	24,909us-gaap_LongTermDebtFairValue
Accrued interest payable	425metr_InterestPayableFairValueDisclosure	325metr_InterestPayableFairValueDisclosure
Commitments to Extend Credit [Member]
Financial liabilities:
Off-balance sheet instruments	0	0
Standby Letters of Credit [Member]
Financial liabilities:
Off-balance sheet instruments	0	0
Quoted Prices in Active Markets for Identical Assets, Level 1 [Member]
Financial assets:
Cash and cash equivalents	58,398	42,832
Securities	0	0
Loans held for sale	0	0
Loans, net	0	0
Restricted investments in bank stock	0	0
Accrued interest receivable	7,644	7,349
Financial liabilities:
Deposits	0	0
Short-term borrowings	246,986	333,475
Long-term debt	0
Accrued interest payable	425	325
Quoted Prices in Active Markets for Identical Assets, Level 1 [Member] \| Commitments to Extend Credit [Member]
Financial liabilities:
Off-balance sheet instruments	0	0
Quoted Prices in Active Markets for Identical Assets, Level 1 [Member] \| Standby Letters of Credit [Member]
Financial liabilities:
Off-balance sheet instruments	0	0
Significant Other Observable Inputs, Level 2 [Member]
Financial assets:
Cash and cash equivalents	0	0
Securities	809,081	847,961
Loans held for sale	0	0
Loans, net	0	0
Restricted investments in bank stock	0	0
Accrued interest receivable	0	0
Financial liabilities:
Deposits	0	0
Short-term borrowings	0	0
Long-term debt	0
Accrued interest payable	0	0
Significant Other Observable Inputs, Level 2 [Member] \| Commitments to Extend Credit [Member]
Financial liabilities:
Off-balance sheet instruments	0	0
Significant Other Observable Inputs, Level 2 [Member] \| Standby Letters of Credit [Member]
Financial liabilities:
Off-balance sheet instruments	0	0
Significant Unobservable Inputs, Level 3 [Member]
Financial assets:
Cash and cash equivalents	0	0
Securities	0	0
Loans held for sale	5,628	5,037
Loans, net	1,985,025	1,980,846
Restricted investments in bank stock	16,021	15,223
Accrued interest receivable	0	0
Financial liabilities:
Deposits	2,413,948	2,383,085
Short-term borrowings	0	0
Long-term debt	24,909
Accrued interest payable	0	0
Significant Unobservable Inputs, Level 3 [Member] \| Commitments to Extend Credit [Member]
Financial liabilities:
Off-balance sheet instruments	0	0
Significant Unobservable Inputs, Level 3 [Member] \| Standby Letters of Credit [Member]
Financial liabilities:
Off-balance sheet instruments	0	0
Carrying Amount [Member]
Financial assets:
Cash and cash equivalents	58,398	42,832
Securities	809,107	853,032
Loans held for sale	5,613	4,996
Loans, net	1,977,955	1,973,536
Restricted investments in bank stock	16,021	15,223
Accrued interest receivable	7,644	7,349
Financial liabilities:
Deposits	2,411,519	2,380,672
Short-term borrowings	246,986	333,475
Long-term debt	25,000
Accrued interest payable	425	325
Carrying Amount [Member] \| Commitments to Extend Credit [Member]
Financial liabilities:
Off-balance sheet instruments	0	0
Carrying Amount [Member] \| Standby Letters of Credit [Member]
Financial liabilities:
Off-balance sheet instruments	$ 0	$ 0

Interest Payable, Fair Value Disclosure

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- Definition

Interest Receivable, Fair Value Disclosure

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- Definition

Marketable Securities, Fair Value Disclosure

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Restricted Investments in Bank Stock, Fair Value Disclosure

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- Definition

Short-term Borrowing and Repurchase Agreements, Fair Value Disclosure

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

+ Details

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- Definition

The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=35750535&loc=d3e13433-108611

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

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Balance Type:	debit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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