Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tax benefits recorded on stock based compensation	$ 23.1	$ 18.9
Aggregate intrinsic value of options exercisable	$ 900.3
Weighted average remaining contractual term of options exercisable (in years)	5 years 1 month 6 days
Minimum \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting provisions (in years)	1 year
Minimum \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting provisions (in years)	1 year
Maximum \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting provisions (in years)	5 years
Maximum \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of vesting provisions (in years)	4 years

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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.

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