Incentive Stock Options And Non-Qualified Stock Options Granted Price At Fair Value Of Common Stock, Percentage

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- Definition

Shares issued under other than stock options plan counted in long-term incentive plan.

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Shares issued under stock options plan counted in long-term incentive plan.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate number of common shares reserved for future issuance.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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- Definition

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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- Definition

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.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of share options (or share units) exercised during the current period.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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Long-term Incentive Plans (Narrative) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
ISO and NQSO granted price at fair value of common stock, percentage	100.00%
Options expired or canceled	222,700	767,406	2,247,862
Stock option awards exercised	0	400,000	0
Number of Options, Outstanding	2,325,300	2,548,000	3,715,406	5,963,268
Omnibus Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of shares of common stock reserved and available for issuance	10,000,000
Shareholder approved increase in common stock reserved and available for issuance	14,000,000
Shares issued under Omnibus Plan in connection with stock options, count	1
Shares/units available for future grants	5,663,974
Omnibus Plan [Member] \| After May 1, 2012 Amendment [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under Omnibus Plan in connection with other than stock options, count	1.28
Omnibus Plan [Member] \| Prior To May 1, 2012 Amendment [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under Omnibus Plan in connection with other than stock options, count	2
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	481,636	3,263,472	449,931
Forfeited	800	123,120	2,968,530
Stock issued during period, value, restricted stock award, gross	$ 4	$ 39
Share-based compensation expense (benefit)	20	18	$ 11
Tax benefit related to restricted share awards		$ 2	$ 1
Tax charge related to restricted share awards	2
Unrecognized compensation cost	$ 20
Expected to be recognized as expense over a weighted average period, years	1 year 9 months 29 days
Other than options outstanding	4,727,319	6,358,826	3,832,115	7,320,110
Restricted Stock [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long-term incentive awards vesting period, years	3 years
Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long-term incentive awards vesting period, years	5 years
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense (benefit)			$ 2
Tax benefit related to restricted share awards	$ 2	$ 4	$ 5
Employee Stock Option [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long-term incentive awards expiration period, years	7 years
Long-term incentive awards vesting period, years	4 years
Employee Stock Option [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Long-term incentive awards expiration period, years	10 years
Long-term incentive awards vesting period, years	5 years
Performance Based Awards [Member] \| Key Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted		3,000,000