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Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2014

Share-based Compensation [Abstract]

Target grants performance share

Target grants of performance shares outstanding at December 31, 2014, were as follows:

Grant Date	Performance Period	Target Grant of Shares
February 2012	2012-2014	251,196
March 2013	2013-2015	240,419
February 2014	2014-2016	196,840

Schedule of share-based payment award, performance shares, valuation assumptions

Assumptions used for grants of performance shares issued in 2014, 2013 and 2012 were:

				2014						2013						2012
Grant-date fair value					$41.13						$29.01						$17.18
Blended volatility range	18.94	%	–	20.43		%	16.10	%	–	19.39		%	24.29	%	–	25.81		%
Risk-free interest rate range	.03	%	–	.74		%	.09	%	–	.40		%	.10	%	–	.35		%
Discounted dividends per share					$2.15						$2.12						$1.19

Summary of the status of the performance share awards

A summary of the status of the performance share awards for the year ended December 31, 2014, was as follows:

	Number of Shares		Weighted Average Grant-Date Fair Value
Nonvested at beginning of period	749,991		$	21.99
Granted	196,840		41.13
Additional performance shares earned	236,699		19.99
Vested	(491,213	)	19.99
Forfeited	(3,862	)	29.01
Nonvested at end of period	688,455		$	28.16

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Target grants performance shares [Table Text Block]

+ References

No definition available.

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Tabular disclosure of components of a stock option or other award plan under which equity-based compensation is awarded to employees, typically comprised of the amount of unearned compensation (deferred compensation cost), compensation expense, and changes in the quantity and fair value of the shares (or other type of equity) granted, exercised, forfeited, and issued and outstanding pertaining to that plan. Disclosure may also include nature and general terms of such arrangements that existed during the period and potential effects of those arrangements on shareholders, effect of compensation cost arising from equity-based payment arrangements on the income statement, method of estimating the fair value of the goods or services received, or the fair value of the equity instruments granted, during the period, cash flow effects resulting from equity-based payment arrangements and, for registrants that accelerate vesting of out of the money share options, reasons for the decision to accelerate.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

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Tabular disclosure of the changes in outstanding nonvested performance-based units.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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