v2.4.0.8

Stock-Based Compensation (Tables) | 3 Months Ended
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Mar. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] |
Schedule of Share-based Compensation, Activity [Table Text Block] | A summary of our performance share unit activity for the three months ended March 31, 2014, is as follows:
| Number of Performance Share Units |  | Weighted Average Grant-Date Fair Value
Nonvested — December 31, 2013 | 449,798 |  |  | $ | 21.25 |
Granted | 461,393 |  |  | $ | 22.56 |
Forfeited | — |  |  | $ | — |
Vested | 15,312 |  | (1) | $ | 21.25 |
Nonvested — March 31, 2014 | 895,879 |  |  | $ | 21.92 |
___________
(1) | In accordance with the applicable performance share unit agreements, performance share units granted to employees who meet the retirement eligibility requirements stipulated in the Equity Plan are fully vested upon the later of the date on which the employee becomes eligible to retire or one-year anniversary of the grant date.
Schedule of Non-Qualified Stock Option Activity | A summary of all of our non-qualified stock option activity for the three months ended March 31, 2014, is as follows:
| Number of Shares |  | Weighted Average Exercise Price |  | Weighted Average Remaining Term (in years) |  | Aggregate Intrinsic Value (in millions)
Outstanding — December 31, 2013 | 14,114,289 |  |  | $ | 18.25 |  |  | 3.1 |  | $ | 36 |
Granted | — |  |  | $ | — |  |  |  |  |
Exercised | 184,931 |  |  | $ | 15.56 |  |  |  |  |
Forfeited | — |  |  | $ | — |  |  |  |  |
Expired | 1,500 |  |  | $ | 17.39 |  |  |  |  |
Outstanding — March 31, 2014 | 13,927,858 |  |  | $ | 18.29 |  |  | 2.8 |  | $ | 48 |
Exercisable — March 31, 2014 | 13,012,308 |  |  | $ | 18.50 |  |  | 2.5 |  | $ | 43 |
Vested and expected to vest – March 31, 2014 | 13,871,693 |  |  | $ | 18.30 |  |  | 2.8 |  | $ | 48 |
Schedule of Assumptions Used to Estimate Fair Value for Options | Certain assumptions were used in order to estimate fair value for options as noted in the following table:
| 2013
Expected term (in years)(1) | 6.5 |  |
Risk-free interest rate(2) | 1.4 |  | %
Expected volatility(3) | 25.6 |  | %
Dividend yield(4) | — |  |
Weighted average grant-date fair value (per option) | $ | 5.31 |  |
___________
(1) | Expected term calculated using the simplified method prescribed by the SEC due to the lack of sufficient historical exercise data on the grant date to provide a reasonable basis to estimate the expected term.
(2) | Zero Coupon U.S. Treasury rate or equivalent based on expected term.
(3) | Volatility calculated using the implied volatility of our exchange traded stock options.
(4) | We have never paid cash dividends on our common stock, and we do not anticipate any cash dividend payments on our common stock in the near future.
Schedule of Restricted Stock and Restricted Stock Unit Activity | A summary of our restricted stock and restricted stock unit activity for the three months ended March 31, 2014, is as follows:
| Number of Restricted Stock Awards |  | Weighted Average Grant-Date Fair Value
Nonvested — December 31, 2013 | 4,431,841 |  |  | $ | 16.45 |
Granted | 1,764,446 |  |  | $ | 19.11 |
Forfeited | 25,977 |  |  | $ | 17.03 |
Vested | 1,434,614 |  |  | $ | 15.07 |
Nonvested — March 31, 2014 | 4,735,696 |  |  | $ | 17.86 |

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- Definition Tabular disclosure of share-based compensation plans that may be presented in a single table for outstanding, vested and expected to vest, and exercisable awards. The information that may be disclosed in this table may include, but is not limited to, number of shares, weighted average exercise price, weighted average remaining contractual life, and aggregate intrinsic value. + References No definition available. + Details
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- Definition Disclosure of the number and weighted-average grant date fair value for restricted stock and restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year. + References No definition available. + Details
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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired 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=6415400&loc=d3e5070-113901 + Details
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- Definition 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=6415400&loc=d3e5070-113901 + Details
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