The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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-Publisher FASB
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-Section 50
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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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-Topic 718
-SubTopic 10
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-Paragraph 2
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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-Publisher FASB
-Name Accounting Standards Codification
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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-Publisher FASB
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-Topic 718
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-Paragraph 2
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- Definition

Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

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Stockholders' Equity - Restricted Stock Units (Details) - USD ($) $ / shares in Units, shares in Millions	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Unvested restricted stock units
Shares
Nonvested beginning balance (in shares)	1.8	1.8	2.7
Granted	0.7
Vested	(1.4)
Forfeited	(0.2)
Nonvested ending balance (in shares)	1.8
Weighted Average Grant Date Fair Value
Weighted average grant date fair value beginning of period (in dollars per share)	$ 69.19
Granted	142.87
Vested	68.89
Forfeited	83.09
Weighted average grant date fair value end of period (in dollars per share)	$ 95.06
Aggregate intrinsic value		$ 276,000,000.0	$ 319,000,000.0
Total vest date fair value	$ 195,900,000
Performance Shares
Weighted Average Grant Date Fair Value
Total vest date fair value	$ 0