v2.4.0.8

Share-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2013
Stock options |
Share-based compensation disclosures |
Stock option transactions under various stock-based employee compensation plans |
Options |  | Shares |  | Weighted- Average Exercise Price |  | Weighted- Average Remaining Contractual Term |  | Aggregate Intrinsic Value |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
|  | (In thousands, except exercise price) |
Options outstanding as of December 31, 2012 |  |  | 22,464 |  | $ | 20.53 |  |  |  |  |  |
Granted |  |  | 63 |  |  | 16.06 |  |  |  |  |  |
Exercised |  |  | (577 | ) |  | 9.34 |  |  |  |  |  |
Surrendered(1) |  |  | — |  |  | 9.18 |  |  |  |  |  |
Forfeited |  |  | (3,564 | ) |  | 19.36 |  |  |  |  |  |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Options outstanding as of December 31, 2013 |  |  | 18,386 |  | $ | 21.10 |  | 3.22 years |  | $ | 51,136 |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Options exercisable as of December 31, 2013 |  |  | 17,837 |  | $ | 21.10 |  | 3.06 years |  | $ | 50,818 |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
(1) Represents unexercised vested stock options that were surrendered by employees, to satisfy the option exercise price and related income taxes. See related discussion at Note 15—Common Shares.
Schedule of weighted-average assumptions used to value awards granted during the period |
|  | Year Ended December 31,
--- | --- | ---
|  | 2013 |  | 2012 |  | 2011
Weighted average fair value of options granted |  | $6.05 |  | $9.40 |  | $6.24
Weighted average risk free interest rate |  | 0.79% |  | 0.63% |  | 0.65%
Dividend yield |  | 0.84% |  | 0% |  | 0%
Volatility(1) |  | 51.01% |  | 55.74% |  | 51.09%
Expected life |  | 4.0 years |  | 4.0 years |  | 4.0 years
(1) Expected volatilities are based on implied volatilities from publicly traded options to purchase Nabors' common shares, historical volatility of Nabors' common shares and other factors.
Unvested stock options |
Unvested Stock Options |  | Outstanding |  | Weighted-Average Grant-Date Fair Value |
--- | --- | --- | --- | --- | ---
|  | (In thousands, except fair value) |
Unvested as of December 31, 2012 |  |  | 1,626 |  | $ | 5.62 |
Granted |  |  | 63 |  |  | 6.05 |
Vested |  |  | (1,075 | ) |  | 3.97 |
Forfeited |  |  | (65 | ) |  | 5.47 |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Unvested as of December 31, 2013 |  |  | 549 |  | $ | 8.88 |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Restricted Stock |
Share-based compensation disclosures |
Unvested restricted stock |
Restricted stock |  | Outstanding |  | Weighted-Average Grant-Date Fair Value |
--- | --- | --- | --- | --- | ---
|  | (In thousands, except fair value) |
Unvested as of December 31, 2012 |  |  | 1,781 |  | $ | 23.42 |
Granted |  |  | 4,493 |  |  | 16.43 |
Vested |  |  | (2,262 | ) |  | 18.48 |
Forfeited |  |  | (248 | ) |  | 20.07 |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Unvested as of December 31, 2013 |  |  | 3,764 |  | $ | 18.26 |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Restricted Stock Based on Market Conditions |
Share-based compensation disclosures |
Schedule of weighted-average assumptions used to value awards granted during the period | The grant date fair value of these awards was based on a Monte Carlo model, using the following assumptions during 2013:
Risk free interest rate |  |  | 0.41 | %
Expected volatility |  |  | 46.00 | %
Closing stock price |  | $ | 16.53 |
Expected term (in years) |  |  | 2.82 |
Unvested restricted stock |
Market based restricted stock |  | Outstanding |  | Weighted-Average Grant-Date Fair Value |
--- | --- | --- | --- | --- | ---
|  | (In thousands, except fair value) |
Outstanding as of December 31, 2012 |  |  | — |  | $ | — |
Granted |  |  | 354 |  |  | 10.42 |
Vested |  |  | — |  |  | — |
Forfeited |  |  | — |  |  | — |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Outstanding as of December 31, 2013 |  |  | 354 |  | $ | 10.42 |
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​

X
- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for unvested share options (or share units) that were outstanding at the beginning and end of the year, the number of share options or share units that were granted, vested, and 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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