Share-Based Payments (Exercise Range) (Details) $ / shares in Units, $ in Thousands	6 Months Ended
Jun. 30, 2017 USD ($) $ / shares shares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding (in shares)	106,183
Number Outstanding, Aggregate intrinsic value \| $	$ 12,622
Number Exercisable (in shares)	55,826
Options Exercisable, Aggregate intrinsic value \| $	$ 7,732
Closing stock price (in usd per share) \| $ / shares	$ 319.62
Exercise Price $255.13
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share) \| $ / shares	255.13
Exercise Price $208.05
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share) \| $ / shares	$ 208.05
Employee Stock Option \| Exercise Price $255.13
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding (in shares)	13,018
Weighted- Average Remaining Contractual Life (in years)	9 months 18 days
Number Exercisable (in shares)	13,018
Employee Stock Option \| Exercise Price $208.05
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding (in shares)	6,000
Weighted- Average Remaining Contractual Life (in years)	1 year
Number Exercisable (in shares)	6,000
SAR \| Exercise Price $114.64
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share) \| $ / shares	$ 114.64
Number Outstanding (in shares)	11,900
Weighted- Average Remaining Contractual Life (in years)	1 year 7 months 6 days
Number Exercisable (in shares)	11,900
SAR \| Exercise Price $132.56
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share) \| $ / shares	$ 132.56
Number Outstanding (in shares)	21,968
Weighted- Average Remaining Contractual Life (in years)	4 years 6 months
Number Exercisable (in shares)	13,962
SAR \| Exercise Price $210.22
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share) \| $ / shares	$ 210.22
Number Outstanding (in shares)	28,450
Weighted- Average Remaining Contractual Life (in years)	6 years 4 months 24 days
Number Exercisable (in shares)	6,850
SAR \| Exercise Price $216.48
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share) \| $ / shares	$ 216.48
Number Outstanding (in shares)	13,132
Weighted- Average Remaining Contractual Life (in years)	8 years 7 months 6 days
Number Exercisable (in shares)	4,096
SAR \| Exercise Price $311.16
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share) \| $ / shares	$ 311.16
Number Outstanding (in shares)	11,512
Weighted- Average Remaining Contractual Life (in years)	9 years 7 months 6 days
Number Exercisable (in shares)	0
SAR \| Exercise Price $310.55
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price (in usd per share) \| $ / shares	$ 310.55
Number Outstanding (in shares)	203
Weighted- Average Remaining Contractual Life (in years)	9 years 9 months 18 days
Number Exercisable (in shares)	0

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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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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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

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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

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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

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Price of a single share of a number of saleable stocks of a company.

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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.

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- Definition

Weighted average remaining contractual term of exercisable stock options, 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)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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