Business Combination, Consideration Transferred, Cash Paid for Each Share of Acquired Entity's Shares, Expected

No definition available.

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- Definition

Business Combination, Consideration Transferred, Equity Interests Issued and Issuable, Number of Shares for Each Share of Acquired Entity's Shares, Expected

+ References

No definition available.

+ Details

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- Definition

Business Combination, Consideration Transferred, Expected Equity Interests Issued and Issuable, Shares

+ References

No definition available.

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- Definition

Debt Instrument, Contingently Issuable Face Amount

+ References

No definition available.

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

No definition available.

+ Details

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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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 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 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

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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Commitments, Contingencies and Other Items (Merger Agreement) (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 15, 2014	Sep. 15, 2014	Jun. 13, 2014	Mar. 14, 2014	Dec. 31, 2014	Mar. 02, 2015	Feb. 10, 2015
Business Acquisition [Line Items]
Common Stock, Par or Stated Value Per Share	$ 1	$ 1						1
Dividends declared, Per common share	$ 1.16	$ 1.12	$ 1.08
Common stock
Business Acquisition [Line Items]
Dividends declared, Per common share				$ 0.29	$ 0.29	$ 0.29	$ 0.29
Platinum
Business Acquisition [Line Items]
Business Acquisition, Transaction Costs	$ 6,700,000							6,700,000
Platinum \| Common stock
Business Acquisition [Line Items]
Number of shares to be issued for acquisition								7,500,000
Cash Election \| Platinum
Business Acquisition [Line Items]
Cash per share	$ 66							66
Share Election \| Platinum
Business Acquisition [Line Items]
Common share per share	0.6504							0.6504
Standard Election \| Platinum
Business Acquisition [Line Items]
Cash per share	$ 35.96							35.96
Common share per share	0.2960							0.2960
Scenario, Forecast
Business Acquisition [Line Items]
Debt Instrument, face amount									300,000,000
Scenario, Forecast \| Platinum
Business Acquisition [Line Items]
Aggregate consideration									1,900,000,000
Business Acquisition, Transaction Costs									$ 10,000,000
Scenario, Forecast \| Platinum
Business Acquisition [Line Items]
Dividends declared, Per common share										$ 10