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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The highest quantity of shares an employee can purchase under the plan per period.

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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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Gross number of share options (or share units) granted during the period.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	6 Months Ended	12 Months Ended
	Sep. 23, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2021	Jun. 30, 2020	Jun. 30, 2019	Dec. 05, 2012
Share-based Compensation [Line Items]
Options granted (shares)				0	0	0
Unrecognized stock-based compensation expense		$ 61.7		$ 61.7
Weighted-average period for recognition (years)				2 years 3 months 18 days
2017 Plan
Share-based Compensation [Line Items]
Number of shares authorized		4,600,000		4,600,000
Shares available for grant		3,600,000		3,600,000
2012 Purchase Plan
Share-based Compensation [Line Items]
Number of shares authorized							2,000,000
Additional shares available for future grant	2,000,000
Maximum number of shares per participant per offering period	5,000
Shares issued under the Plan		2,000,000
President and Chief Executive Officer
Share-based Compensation [Line Items]
Options granted (shares)			700,000
Weighted average grant date fair value of options granted (dollars per share)			$ 13.38
Options and RSUs \| Non-employee director
Share-based Compensation [Line Items]
Service period for award vesting (in years)				1 year
Stock options
Share-based Compensation [Line Items]
Service period for award vesting (in years)				4 years
Award expiration period (in years)				10 years
Stock options \| President and Chief Executive Officer
Share-based Compensation [Line Items]
Award expiration period (in years)				7 years
RSUs
Share-based Compensation [Line Items]
Service period for award vesting (in years)				4 years
Weighted average grant date fair value (dollars per share)			$ 13.69	$ 29.83	$ 27.96	$ 46.62
Fair value of restricted stock units that vested			$ 29.1	$ 22.6	$ 32.4	$ 27.6
RSUs \| Certain executive officers and other senior positions \| Achievement levels based on EPS targets
Share-based Compensation [Line Items]
Vesting weight (percent)				50.00%
RSUs \| Certain executive officers and other senior positions \| Performance based on Nasdaq Healthcare Provider Index
Share-based Compensation [Line Items]
Vesting weight (percent)				50.00%