Beneficial Owner of Common Stock, Percentage

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- Definition

Number Of Shares Of Preferred Stock Per Right

+ References

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- Definition

Period Following the Commencement of a Tender or Exchange Offer, Days

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- Definition

Period Following Determination an Individual has become a Beneficial Owner, In Days

+ References

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- Definition

Period Rights Seperated From Common Stock

+ References

No definition available.

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- Definition

Right Redeemable Price

+ References

No definition available.

+ Details

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- Definition

Terms of Rights Agreement

+ References

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ 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

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- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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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

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-Publisher SEC
-Name Regulation S-X (SX)
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-Section 02
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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.

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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
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-Subparagraph (SX 210.5-02.28)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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- Definition

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

+ References

+ Details

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
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Capital Stock (Details)			12 Months Ended
Capital Stock (Details)	Aug. 07, 2006 $ / shares	Aug. 07, 2006 $ / shares $ / Right	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares	Dec. 31, 2013 USD ($)	Feb. 23, 2016 shares	Dec. 16, 2014 USD ($)	Mar. 08, 2012 USD ($)	May. 31, 2011 USD ($)	May. 02, 2011 USD ($)
Equity, Class of Treasury Stock [Line Items]
Common stock, shares issued \| shares			153,776,000	152,451,000
Treasury stock, shares \| shares			76,458,000	74,378,000		76,700,096
Common stock, outstanding \| shares			77,318,000
Purchase rate of rights	0.001
Preferred stock, par value (usd per share) \| $ / shares	$ 0.001	$ 0.001	$ 0.001	$ 0.001
Purchase price, per right \| $ / shares	$ 170.00	$ 170.00
Period rights separated from common stock		10 days
Period following the commencement of a tender or exchange offer		10 days
Period following determination an individual has become a beneficial owner		10 days
Price per redeemable right \| $ / Right		0.01
Stock repurchase program authorized amount \| $			$ 400,000,000.0				$ 257,800,000	$ 323,700,000.0	$ 300,000,000	$ 300,000,000
Treasury stock value acquired cost method \| $			113,287,000	$ 161,908,000	$ 87,119,000
Stock repurchase program remaining authorized repurchase amount \| $			$ 306,200,000	$ 400,000,000			$ 400,000,000.0
Benefical Owner of Common Stock Percentage [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement		15.00%
Beneficial owner of common stock, percentage	15.00%	15.00%
Percentage of Common Stock Owned [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement		10.00%
Percentage of Rights Owned By Individual Beneficial Owner Not Deemed Acquiring Person [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement		20.00%
Percentage of Assets Sold [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement		50.00%
Beneficial Owner of a Percentage of Outstanding Common Stock [Member]
Equity, Class of Treasury Stock [Line Items]
Terms of rights agreement		50.00%
Stock Repurchase Program [Member]
Equity, Class of Treasury Stock [Line Items]
Treasury stock shares acquired \| shares			1,700,000	3,000,000
Treasury stock value acquired cost method \| $			$ 93,800,000	$ 137,800,000