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Stock-Based Compensation Plans - Employee Stock Purchase Plan (Details) - Employee Stock Purchase Plan shares in Millions	6 Months Ended
	Jun. 30, 2021 $ / shares shares
Stock-Based Compensation Plans - Disclosures
Share purchases under employee stock purchase plan (in shares)	0.7
Weighted-average fair value of discount on employee stock purchase plan (in dollars per share) | $ / shares	$ 16.57
Shares available to be issued under employee stock purchase plan (in shares)	4.3

X

- Definition

The difference between the maximum number of shares authorized for issuance under the Employee Stock Purchase Plan (including the effects of amendments) and the number of shares already issued under the plan, net of adjustments.

+ References

No definition available.

+ Details

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X

- Definition

The weighted-average fair value per share of the discount applied to employee purchases under the employee stock purchase plan during the period.

+ References

No definition available.

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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.

+ References

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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