Common Stock Dividend Declared, Percent

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- Definition

Common Stock, Subscriptions During Period, Shares

+ References

No definition available.

+ Details

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- Definition

Common Stock, Subscriptions During Period, Value

+ References

No definition available.

+ Details

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- Definition

The percentage of common stock held in the Voting Trust

+ References

No definition available.

+ Details

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- Definition

Stockholders' Equity Note, Percent of Entity Owned by Current and Retired Employees

+ References

No definition available.

+ Details

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- Definition

Face amount or stated value per share of common stock.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

+ Details

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

+ Details

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- Definition

The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

+ Details

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- Definition

Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

+ Details

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Period Type:	instant

- 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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

+ Details

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- Definition

Number of shares of common and preferred stock retired from treasury during the period.

+ References

+ Details

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Capital Stock Par Value of Stock (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 10, 2004
Class of Stock [Line Items]
Stockholders' Equity Note, Percent of Entity Owned by Current and Retired Employees	100.00%
Common stock stated value per share (USD per share)	$ 20	$ 20
Common stock, subscriptions ( in shares)	806,811
Common shares subscribed (in dollars)	$ 16,136
Treasury Stock Transactions, Excluding Value of Shares Reissued [Abstract]
Shares of common stock purchased	752,983us-gaap_TreasuryStockSharesAcquired	638,647us-gaap_TreasuryStockSharesAcquired	558,599us-gaap_TreasuryStockSharesAcquired
Shares of common stock retired	780,077us-gaap_TreasuryStockSharesRetired	681,637us-gaap_TreasuryStockSharesRetired	658,890us-gaap_TreasuryStockSharesRetired
Preferred stock shares authorized				10,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock par or stated value per share (USD per share)				$ 0.01
Preferred stock outstanding (in shares)	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock dividend declared, percent		2.50%	20.00%
Common Stock
Class of Stock [Line Items]
Percentage Ownership in Voting Trust	83.00%