Number of share-based compensation plans maintained by the company.

No definition available.

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- Definition

Number of outstanding shares authorized eligible to be repurchased under an established share-based compensation plan.

+ References

No definition available.

+ Details

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- Definition

Date the equity-based award vests, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

Price of shares obligated to be repurchased expressed as a percentage of its book value

+ References

No definition available.

+ Details

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- Definition

Period which an executive's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.

+ References

No definition available.

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- References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 14
-Section F

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- Definition

The total fair value of shares issued during the period under a deferred compensation arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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

Number of share instruments newly issued under a share-based compensation plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Details

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Stock Purchase and Option Plans (Details) $ / shares in Units, $ in Thousands						12 Months Ended
	Feb. 05, 2016 USD ($) $ / shares shares	May. 12, 2015 $ / shares shares	Feb. 04, 2015 USD ($) $ / shares shares	May. 08, 2014 $ / shares shares	May. 07, 2013 $ / shares shares	Dec. 31, 2015 USD ($) Plan shares	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share based compensation plans \| Plan						1
Restricted Stock Units (RSUs) [Member] \| Outside Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost charged against income \| $						$ 460	$ 440	$ 440
Restricted Stock Units (RSUs) [Member] \| Class B [Member] \| Outside Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total value of shares issued \| $						$ 480	$ 440	$ 440
Summary of stock Issuances [Abstract]
Number of shares issued (in shares)		21,252		17,237	18,106
Vesting Date		May 12, 2016		May 08, 2015	May 07, 2014
Period		7/1/2015 - 6/30/2016		7/1/2014 - 6/30/2015	7/1/2013 - 6/30/2014
Value of each share issued (in dollars per share) \| $ / shares		$ 22.59		$ 25.53	$ 24.30
Restricted Stock Units (RSUs) [Member] \| Class B [Member] \| Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)			36,646
Total value of shares issued \| $			$ 853
Summary of stock Issuances [Abstract]
Value of each share issued (in dollars per share) \| $ / shares			$ 23.29
Period restricted stocks will vest ratably from date of grant			3 years
Restricted Stock Units (RSUs) [Member] \| Class B [Member] \| Executives [Member] \| Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)	47,333
Total value of shares issued \| $	$ 1,103
Summary of stock Issuances [Abstract]
Value of each share issued (in dollars per share) \| $ / shares	$ 23.30
Period restricted stocks will vest ratably from date of grant	3 years
1981 Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of shares obligated to be repurchased, percentage of book value						90.00%
1981 Stock Purchase Plan [Member] \| Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of outstanding shares eligible for repurchase (in shares)						121,286
1981 Stock Purchase Plan [Member] \| Class B [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of outstanding shares eligible for repurchase (in shares)						339,546