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Share-Based Compensation Plans - Summary of options outstanding and exercisable (Details) shares in Thousands | 12 Months Ended
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Dec. 31, 2015 $ / shares shares
Share options outstanding and share options exercisable |
Share options, outstanding (in shares) | shares | 837
Share options exercisable (in shares) | shares | 837
19.54 - 25.51 |
Share options outstanding and share options exercisable |
Share options, outstanding (in shares) | shares | 79
Weighted-average remaining contractual life (years) | 2 years 2 months 5 days
Weighted average exercise price of share options outstanding (in dollars per share) | $ 20.18
Share options exercisable (in shares) | shares | 79
Weighted average remaining contractual life of share options exercisable (in years) | 2 years 2 months 5 days
Weighted average exercise price of share options exercisable (in dollars per share) | $ 20.18
Exercise price range, minimum | 19.54
Exercise price range, maximum | $ 25.51
25.52 - 32.53 |
Share options outstanding and share options exercisable |
Share options, outstanding (in shares) | shares | 25
Weighted-average remaining contractual life (years) | 1 year 11 months 5 days
Weighted average exercise price of share options outstanding (in dollars per share) | $ 29.15
Share options exercisable (in shares) | shares | 25
Weighted average remaining contractual life of share options exercisable (in years) | 1 year 11 months 5 days
Weighted average exercise price of share options exercisable (in dollars per share) | $ 29.15
Exercise price range, minimum | 25.52
Exercise price range, maximum | $ 32.53
32.54 - 36.88 |
Share options outstanding and share options exercisable |
Share options, outstanding (in shares) | shares | 160
Weighted-average remaining contractual life (years) | 1 year 1 month 21 days
Weighted average exercise price of share options outstanding (in dollars per share) | $ 35.77
Share options exercisable (in shares) | shares | 160
Weighted average remaining contractual life of share options exercisable (in years) | 1 year 1 month 21 days
Weighted average exercise price of share options exercisable (in dollars per share) | $ 35.77
Exercise price range, minimum | 32.54
Exercise price range, maximum | $ 36.88
36.89 - 43.44 |
Share options outstanding and share options exercisable |
Share options, outstanding (in shares) | shares | 247
Weighted-average remaining contractual life (years) | 3 years 1 month 13 days
Weighted average exercise price of share options outstanding (in dollars per share) | $ 39.32
Share options exercisable (in shares) | shares | 247
Weighted average remaining contractual life of share options exercisable (in years) | 3 years 1 month 13 days
Weighted average exercise price of share options exercisable (in dollars per share) | $ 39.32
Exercise price range, minimum | 36.89
Exercise price range, maximum | $ 43.44
43.45 - 52.93 |
Share options outstanding and share options exercisable |
Share options, outstanding (in shares) | shares | 326
Weighted-average remaining contractual life (years) | 2 years 5 months 16 days
Weighted average exercise price of share options outstanding (in dollars per share) | $ 48.26
Share options exercisable (in shares) | shares | 326
Weighted average remaining contractual life of share options exercisable (in years) | 2 years 5 months 16 days
Weighted average exercise price of share options exercisable (in dollars per share) | $ 48.26
Exercise price range, minimum | 43.45
Exercise price range, maximum | $ 52.93

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- Definition The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied. + 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)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range. + 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 (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (e)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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