Consolidated Statements of Changes in Shareholders’ Equity (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement of Stockholders' Equity [Abstract]
Cash dividends per share (usd per share)	$ 0.10	$ 0.08
Stock-based compensation plans, issuance of stock, shares		27,962
Stock-based compensation plans, forfeited, shares	6,268
Compensation expense, issuance of stock	$ 303	$ 240
Issuance of treasury stock, shares	53,367	2,461
Acquisition of treasury stock, shares		14,221

This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66904339&loc=d3e4534-113899

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=65896087&loc=d3e11149-113907

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Balance Type:	credit
Period Type:	duration

- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

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Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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Period Type:	duration

- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
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-Name Accounting Standards Codification
-Topic 505
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-Paragraph 1
-Subparagraph (SX 210.3-04)
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- Definition

Number of shares (or other type of equity) forfeited during the period.

+ References

No definition available.

+ Details

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- Definition

Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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-Paragraph 1
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