Common Stock [Line Items]

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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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

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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- Definition

Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

+ References

+ Details

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- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

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- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, 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 maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands					3 Months Ended								12 Months Ended
	Mar. 31, 2016	Mar. 15, 2016	Jan. 28, 2016	Dec. 30, 2015	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	May. 29, 2014
Common Stock [Line Items]
Dividends, Common Stock, Cash				$ 11,900									$ 47,059	$ 44,556	$ 42,049
Common Stock, Dividends, Per Share, Declared					$ 0.295	$ 0.295	$ 0.295	$ 0.280	$ 0.280	$ 0.280	$ 0.280	$ 0.265	$ 1.165	$ 1.105	$ 1.045
Common Stock, Par or Stated Value Per Share					$ 1				$ 1				$ 1	$ 1
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized																1,700,000.0
Restricted Stock \| Minimum
Common Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period													1 year
Restricted Stock \| Maximum
Common Stock [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period													3 years
Scenario, Forecast
Common Stock [Line Items]
Dividends Payable, Date to be Paid	Mar. 31, 2016
Dividends Payable, Date of Record		Mar. 15, 2016
Subsequent Event
Common Stock [Line Items]
Dividends Payable, Date Declared			Jan. 28, 2016
Common Stock, Dividends, Per Share, Declared			$ 0.295