Stock-Based Compensation and Stockholders' Equity - Outstanding at End of Period (Details) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	49,574	176,724
Options weighted average exercise price (in USD per share)	$ 21.37	$ 22.57
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding (in shares)	2,126,661	2,414,111
Weighted average exercise price (in USD per share)	$ 49.87	$ 42.55
Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding (in shares)	417,069	500,482
Weighted average exercise price (in USD per share)	$ 62.20	$ 48.32
Market-based Stock Units (MSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding (in shares)	383,098	446,087
Weighted average exercise price (in USD per share)	$ 76.97	$ 49.37

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.

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 (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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

+ References

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- Definition

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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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120381028&loc=d3e5070-113901

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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-Name Accounting Standards Codification
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