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Options Outstanding and Exercisable - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Information regarding options outstanding and exercisable |  |  |
Options Outstanding, Options | 6,023,101 |  |
Options Outstanding, Weighted Average Remaining Contractual Life in Years | 4 years 7 months 29 days |  |
Options Outstanding, Weighted Average Exercise Price | $ 42.05 |  |
Options Exercisable, Options | 5,610,677 |  |
Options Exercisable, Weighted Average Exercise Price | $ 40.91 |  |
Options, Vested and expected to vest | 6,003,870 |  |
Options, Weighted Average Remaining Contractual Life in Years | 4 years 6 months 20 days |  |
Options, Weighted Average Exercise Price | $ 41.97 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | 19.67 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ 68.55 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value | $ 135.3 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value | $ 132.0 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term | 4 years 4 months 26 days |  |
Market value of common shares | $ 64.36 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number |  | 4,436,990 | 5,011,784
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price |  | $ 45.11 | $ 42.18
Exercise Price Range One [Member] |  |  |
Information regarding options outstanding and exercisable |  |  |
Options Outstanding, Options | 892,111 |  |
Options Outstanding, Weighted Average Remaining Contractual Life in Years | 2 years 1 month 7 days |  |
Options Outstanding, Weighted Average Exercise Price | $ 19.67 |  |
Options Exercisable, Options | 892,111 |  |
Options Exercisable, Weighted Average Exercise Price | $ 19.67 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | 19.67 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ 24.93 |  |
Exercise Price Range Two [Member] |  |  |
Information regarding options outstanding and exercisable |  |  |
Options Outstanding, Options | 930,884 |  |
Options Outstanding, Weighted Average Remaining Contractual Life in Years | 2 years 6 months 15 days |  |
Options Outstanding, Weighted Average Exercise Price | $ 29.42 |  |
Options Exercisable, Options | 930,884 |  |
Options Exercisable, Weighted Average Exercise Price | $ 29.42 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | 24.94 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ 37.39 |  |
Exercise Price Range Three [Member] |  |  |
Information regarding options outstanding and exercisable |  |  |
Options Outstanding, Options | 2,412 |  |
Options Outstanding, Weighted Average Remaining Contractual Life in Years | 3 years 10 months |  |
Options Outstanding, Weighted Average Exercise Price | $ 41.44 |  |
Options Exercisable, Options | 2,412 |  |
Options Exercisable, Weighted Average Exercise Price | $ 41.44 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | 37.40 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ 43.62 |  |
Exercise Price Range Four [Member] |  |  |
Information regarding options outstanding and exercisable |  |  |
Options Outstanding, Options | 2,715,880 |  |
Options Outstanding, Weighted Average Remaining Contractual Life in Years | 5 years 6 months |  |
Options Outstanding, Weighted Average Exercise Price | $ 46.59 |  |
Options Exercisable, Options | 2,515,401 |  |
Options Exercisable, Weighted Average Exercise Price | $ 46.47 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | 43.63 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ 49.86 |  |
Exercise Price Range Five [Member] |  |  |
Information regarding options outstanding and exercisable |  |  |
Options Outstanding, Options | 1,114,654 |  |
Options Outstanding, Weighted Average Remaining Contractual Life in Years | 5 years 1 month 28 days |  |
Options Outstanding, Weighted Average Exercise Price | $ 51.30 |  |
Options Exercisable, Options | 1,114,654 |  |
Options Exercisable, Weighted Average Exercise Price | $ 51.30 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | 49.87 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ 56.09 |  |
Exercise Price Range Six [Member] |  |  |
Information regarding options outstanding and exercisable |  |  |
Options Outstanding, Options | 2,761 |  |
Options Outstanding, Weighted Average Remaining Contractual Life in Years | 8 years 5 months 24 days |  |
Options Outstanding, Weighted Average Exercise Price | $ 60.80 |  |
Options Exercisable, Options | 2,761 |  |
Options Exercisable, Weighted Average Exercise Price | $ 60.80 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | 56.10 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ 62.32 |  |
Exercise Price Range Seven [Member] |  |  |
Information regarding options outstanding and exercisable |  |  |
Options Outstanding, Options | 364,399 |  |
Options Outstanding, Weighted Average Remaining Contractual Life in Years | 8 years 6 months 27 days |  |
Options Outstanding, Weighted Average Exercise Price | $ 66.77 |  |
Options Exercisable, Options | 152,454 |  |
Options Exercisable, Weighted Average Exercise Price | $ 67.27 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit | 62.33 |  |
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit | $ 68.55 |  |

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- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. + 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)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. + 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)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable. + 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)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan. + 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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- Definition As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest. + 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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- 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 number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices. + 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)(i)-(ii) -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 Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, 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 -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for fully vested and expected to vest options 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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- Definition Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding. + 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)(iii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices. + 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)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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