Statements Of Consolidated Common Stockholders' Equity (Shares) (Parenthetical) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Beginning Balance, shares	313,676us-gaap_SharesIssued	310,281us-gaap_SharesIssued	281,854us-gaap_SharesIssued
Shares
Treasury stock acquired, shares	(292)us-gaap_TreasuryStockSharesAcquired	(297)us-gaap_TreasuryStockSharesAcquired	(439)us-gaap_TreasuryStockSharesAcquired
Issued:
Employee stock purchase plan, shares	113	102	73
Long-term incentive plan, shares	1,125	2,037	2,692
Dividend reinvestment, shares	206	272	340
Retirement Savings Plan	1,209	1,281	1,496
Forward Equity Settlement			24,265
Ending Balance, shares	316,037us-gaap_SharesIssued	313,676us-gaap_SharesIssued	310,281us-gaap_SharesIssued
Common Stock [Member]
Beginning Balance, shares	315,983	312,291	283,425
Issued:
Employee stock purchase plan, shares	113	102	73
Long-term incentive plan, shares	1,125	2,037	2,692
Dividend reinvestment, shares	206	272	340
Retirement Savings Plan	1,209	1,281	1,496
Forward Equity Settlement			24,265
Ending Balance, shares	318,636	315,983	312,291
Treasury Stock [Member]
Beginning Balance, shares	(2,307)	(2,010)	(1,571)
Shares
Treasury stock acquired, shares	(292)	(297)	(439)
Issued:
Employee stock purchase plan, shares	0	0	0
Long-term incentive plan, shares	0	0	0
Dividend reinvestment, shares	0	0	0
Retirement Savings Plan	0	0	0
Forward Equity Settlement			0
Ending Balance, shares	(2,599)	(2,307)	(2,010)

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- Definition

Stock Issued During Period Shares Forward Equity Settlement

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No definition available.

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- Definition

Stock issued during period, shares, Retirement Savings Plan.

+ References

No definition available.

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- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

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

+ Details

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- Definition

Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders to reinvest dividends paid to them by the entity on new issues of stock by the entity.

+ References

+ Details

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ 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 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

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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- Definition

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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- Definition

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

+ References

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