Employee Benefit Plans and Stockholders' Equity - Shares Available for Grant and RSU and PSU Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Shares Available for Grant
Vested (shares)		0	0
EIP 2015
Shares Available for Grant
Number of shares available for grant at beginning of period (shares)	4,500	4,900	3,200
Additional shares authorized (shares)			2,200
Granted (shares)	(400)	(500)	(700)
Vested (shares)	0
Forfeited (shares)	100	100	200
Number of shares available for grant at end of period (shares)	4,200	4,500	4,900
EIP 2015 \| RSUs and PSUs
Shares Available for Grant
Number of shares available for grant at end of period (shares)	4,200
Shares
Nonvested at beginning of period (shares)	1,200	1,800	2,700
Granted (shares)	400	500	700
Vested (shares)	(700)	(1,000)	(1,400)
Forfeited (shares)	(100)	(100)	(200)
Nonvested at end of period (shares)	800	1,200	1,800
Weighted Average Grant Date Fair Value
Nonvested at beginning of period (USD per share)	$ 183.51	$ 96.63	$ 69.19
Granted (USD per share)	351.32	300.36	144.37
Vested (USD per share)	137.90	92.07	69.45
Forfeited (USD per share)	279.12	137.44	83.45
Nonvested at end of period (USD per share)	$ 307.86	$ 183.51	$ 96.63
Aggregate Intrinsic Value	$ 411.3	$ 430.6	$ 392.0

Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Vested

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Shares Available for Grant

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No definition available.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event.

+ References

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Net number of non-option equity instruments granted to participants.

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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

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No definition available.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

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