Share based compensation arrangement by share based payment award exercise period after employment termination.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award increase percentage of common stock outstanding.

+ References

No definition available.

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- Definition

Contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB
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-Topic 718
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

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

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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

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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.

+ References

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- Definition

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

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- Definition

Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions			3 Months Ended
	Nov. 09, 2018	Apr. 24, 2018	Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, share Reserve			4,196,193
Shares reserved for issuance increase percentage		3.00%
Share-based compensation expense			$ 6.0	$ 2.7
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense related to unvested stock options not yet recognized			0.0
Term Based Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense related to unvested stock options not yet recognized			$ 107.7
Share-based compensation expense related to unvested awards expected to be recognized over a weighted average period			2 years 3 months 18 days
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense related to unvested awards expected to be recognized over a weighted average period			2 years 4 months 24 days
Stock options, vested			125,000
Unvested restricted stock units outstanding			464,073
Vested restricted stock units outstanding			250,000
Share-based compensation expense related to unvested restricted stock units not yet recognized			$ 11.2
Minimum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period			3 years
Maximum [Member] \| Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period			4 years
HCM Stock Incentive Plan 2007 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares outstanding			2,500
HCM Stock Incentive Plan 2013 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares outstanding			8,104,518
Share based compensation arrangement by share based payment award exercise period after employment termination			90 days
Stock option awards, contractual term			10 years
HCM Stock Incentive Plan 2013 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period			4 years
HCM Stock Incentive Plan 2013 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period			5 years
HCM Equity Incentive Plan 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares outstanding			9,359,755
Restricted stock vesting period		4 years
Share based compensation arrangement by share based payment award exercise period after employment termination		90 days
Stock option awards, contractual term		10 years
Number of shares authorized		13,500,000
Shares available for future grants of equity awards			8,336,438
HCM Global Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option awards, contractual term	10 years
HCM Global Employee Stock Purchase Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	2,500,000