Share Repurchase Program Additional Number Of Shares Authorized To Be Repurchased

No definition available.

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- Details

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- Definition

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

+ References

+ Details

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Period Type:	duration

- 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)

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-Name Regulation S-X (SX)

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

+ Details

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Period Type:	instant

- Definition

The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 5

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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

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-Name Regulation S-X (SX)

-Number 210

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- 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

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-Paragraph 1

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-Name Regulation S-X (SX)

-Number 210

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Number of shares held for each class of treasury stock.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 30

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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

+ Details

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Period Type:	duration

- Definition

Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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Stockholders Equity - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2007
Stockholders Equity [Line Items]
Preferred stock, shares authorized	3,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, par value	$ 1
Dividends paid	$ 0.60	$ 0.46	$ 0.36
Stock repurchase program number of shares authorized to repurchase	3,500,000			3,000,000
Stock repurchase program additional number of shares authorized		2,000,000
Shares repurchased	2,154,783us-gaap_TreasuryStockSharesAcquired	1,771,066us-gaap_TreasuryStockSharesAcquired	852,980us-gaap_TreasuryStockSharesAcquired
Shares repurchased, value	$ 103.8	$ 73.7	$ 22.0
Remaining authorization stock repurchase	2,497,993
Common Class A
Stockholders Equity [Line Items]
Common Stock, shares authorized	14,000,000
Common stock, par value	$ 5
Shares converted into Common Stock	272,184	85,792	1,191,706
Treasury stock, number of shares held	65,190	65,190
Common Stock
Stockholders Equity [Line Items]
Common Stock, shares authorized	120,000,000
Common stock, par value	$ 1
Treasury stock, number of shares held	5,889,073	4,049,408