v3.8.0.1

Stock Incentive Plans (Tables)

12 Months Ended

Dec. 31, 2017

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary Of Stock Option Activity

Option activity for the year ended December 31, 2017 is summarized below (shares in thousands):

	Shares			Weighted Average Exercise Price				Aggregate Intrinsic Value ($ in millions)				Weighted Average Remaining Contractual Term
Outstanding as of December 31, 2016	320			$	17.44
Granted	1			68.60
Exercised	(178	)		13.47
Forfeited	(13	)		62.86
Outstanding as of December 31, 2017	130			$	18.82			$	11			2.7
Exercisable as of December 31, 2017	115			$	13.75			$	10			1.9

Option Grant Pricing Assumptions

The fair value of each option grant is estimated on the date of the grant using the Black-Scholes option-pricing model with the following weighted-average assumptions:

	Year Ended December 31,
	2017		2016		2015 (1)
Expected life (in years)	4.8		4.8		—
Risk-free interest rate	1.9%		1.6%		—
Expected volatility	37.5%		39.0%		—
Expected dividend yield	—		—		—
(1) No options were awarded in the year ended December 31, 2015.

Other Information Pertaining to Stock Option Activity

Other information pertaining to option activity is as follows:

	Year Ended December 31,
	2017				2016				2015 (1)
Weighted-average fair value of options granted	$	68.60			$	59.94			$	—
Total intrinsic value of stock options exercised ($ in millions)	$	12			$	19			$	28
(1) No options were awarded in the year ended December 31, 2015.

Summary of Non-Vested Restricted Stock And Restricted Stock

A summary of the Company's non-vested restricted stock and restricted stock unit shares as of December 31, 2017, and changes during the year ended December 31, 2017, is presented below (shares in thousands):

	Shares			Weighted Average Grant Date Fair Value
Non-vested balance as of December 31, 2016	4,790			$	55.75
Granted	1,412			95.13
Vested	(1,883	)		58.10
Forfeited	(150	)		20.40
Non-vested balance as of December 31, 2017	4,169			$	69.30

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- References

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Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year.

+ 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 (c)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Tabular disclosure for stock option plans. Includes, but is not limited to, outstanding awards at beginning and end of year, grants, exercises, forfeitures, and weighted-average grant date fair value.

+ 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 (d)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions.

+ 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 (f)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Tabular disclosure of the weighted-average grant-date fair value of equity options or other equity instruments granted during the year.

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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