Annual Shareholder Return Multiplier On Absolute Basis, Percentage

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- Definition

Fair Value Inputs, Annual Revenue Multiple Ceiling Achievement, Percentage

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- Definition

Fair Value Inputs, Annual Revenue Multiple Threshold Target, Percentage

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award, Annual Performance Metric, Percentage

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payments, Annual Target Ceiling, Base Percentage

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No definition available.

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- Definition

Amount of cost capitalized for award under share-based payment arrangement.

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

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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

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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No definition available.

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- Definition

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

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

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

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Stock Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended			3 Months Ended		9 Months Ended
	Aug. 31, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense capitalized to inventory				$ 5.1	$ 5.3	$ 13.2	$ 14.3
Shares issued under Employee Stock Purchase Plan (in shares)				0		107,473
Restricted Stock With Service Based Vesting Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares, granted (in shares)						1,844,308
Weighted-average fair value per share granted (in dollars per share)						$ 91.23
Shares, granted (in shares)				0		610,250
Weighted-average fair value per RSU granted (in dollars per share)						$ 36.84
Two Thousand Twenty Two Base Restricted Stock Unit Awards With Performance Conditions [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value per RSU granted (in dollars per share)	$ 81.00
Granted restricted stock units	44,260
March 2019 Base Restricted Stock Unit Awards with Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value per RSU granted (in dollars per share)			$ 94.53
Granted restricted stock units			99,010
Award vesting service period		3 years
Percentage of annual threshold target			75.00%
Percentage of annual ceiling achievement			125.00%
March 2019 Base Restricted Stock Unit Awards with Performance Conditions \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual percentage of shares earned, performance metric			0.00%
March 2019 Base Restricted Stock Unit Awards with Performance Conditions \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual percentage of shares earned, performance metric			200.00%
March 2019 Base Restricted Stock Unit Awards with Market Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value per RSU granted (in dollars per share)			$ 143.92
Granted restricted stock units			99,010
Award vesting service period		3 years
Base percentage of annual target ceiling			100.00%
March 2019 Base Restricted Stock Unit Awards with Market Conditions \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual percentage of shares earned, performance metric			0.00%
Percentage of Annual TSR multiplier on absolute basis			50.00%
March 2019 Base Restricted Stock Unit Awards with Market Conditions \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual percentage of shares earned, performance metric			200.00%