Percentage of Stock Award Subject to Vesting

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- Definition

Share based compensation arrangement by share based payment award, award vesting date.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment other than options expiration date.

+ References

No definition available.

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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).

+ 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
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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).

+ References

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- Definition

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

+ 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
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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

Number of shares authorized for issuance under share-based payment arrangement.

+ 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
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ 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
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

+ Details

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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.

+ 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
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ 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
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Number of non-vested options forfeited.

+ References

No definition available.

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Share-Based Compensation Plans - Additional Information (Detail) - $ / shares		3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 06, 2018	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2014
Stock Options \| Chief Executive Officer \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options awarded		0	0	0	0
Unvested stock options forfeited		0	0	0	0
Stock Options \| Chief Executive Officer \| Share-based Compensation Award, Tranche 2 \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options awarded						300,000
Stock Options \| Chief Executive Officer \| Vesting Schedule One \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vested and expected to vest	100,000
Stock options forfeited	100,000
Vesting date				Dec. 31, 2018
Stock Options \| Chief Executive Officer \| Vesting Schedule Two and Three \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vested and expected to vest	200,000
Stock Options \| Chief Executive Officer \| Vesting Schedule Two \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vested and expected to vest	100,000
Vesting date				Dec. 31, 2019
Stock Options \| Chief Executive Officer \| Vesting Schedule Three \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vested and expected to vest	100,000
Vesting date				Dec. 31, 2020
Time Based Option Award \| Chief Executive Officer \| Vesting Schedule One \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vested and expected to vest		100,000		100,000
Vesting date				Dec. 31, 2018
Time Based Option Award \| Chief Executive Officer \| Vesting Schedule Two \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vested and expected to vest		100,000		100,000
Vesting date				Dec. 31, 2019
Time Based Option Award \| Chief Executive Officer \| Vesting Schedule Three \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vested and expected to vest		100,000		100,000
Vesting date				Dec. 31, 2020
Expiration date				Dec. 31, 2027
Time Based Option Award \| Chief Executive Officer \| Share-based Compensation Award, Tranche 3 \| Employment Agreement
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted				300,000
Strike price per share				$ 50
Restricted Stock Units \| Key Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted		0	0	175,498	0
Weighted average fair value per share				$ 30.18
Restricted Stock Units \| Key Employees \| Share-based Compensation Award, Tranche 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date				Jun. 18, 2022
Percentage of shares vested on each anniversary of the grant date				20.00%
Restricted Stock Units \| Key Employees \| Share-based Compensation Award, Tranche 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date				Jun. 18, 2023
Percentage of shares vested on each anniversary of the grant date				30.00%
Restricted Stock Units \| Key Employees \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date				Jun. 18, 2021
Percentage of shares vested on each anniversary of the grant date				10.00%
Restricted Stock Units \| Key Employees \| Share-based Compensation Award, Tranche 4
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date				Jun. 18, 2024
Percentage of shares vested on each anniversary of the grant date				40.00%
Restricted Stock \| Key Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, vested and expected to vest		27,117		27,117
Number of shares granted		0	0	36,180	38,778
Weighted average fair value per share				$ 35.82	$ 40.57
Shares vested				9,063	11,843
Restricted Stock \| Key Employees \| Share-based Compensation Award, Tranche 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date				Jan. 01, 2021	Jan. 01, 2020
Percentage of shares vested on each anniversary of the grant date				16.50%	16.50%
Restricted Stock \| Key Employees \| Vesting Schedule Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date				Mar. 15, 2022	Mar. 15, 2021
Percentage of shares vested on each anniversary of the grant date				100.00%	100.00%
Percentage of stock award subject to vesting				50.00%	50.00%
Restricted Stock \| Key Employees \| Share-based Compensation Award, Tranche 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date				Jan. 01, 2022	Jan. 01, 2021
Percentage of shares vested on each anniversary of the grant date				17.00%	17.00%
Restricted Stock \| Key Employees \| Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting date				Jan. 01, 2020	Jan. 01, 2019
Percentage of shares vested on each anniversary of the grant date				16.50%	16.50%
Restricted Stock \| Non Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted		19,275	7,049	50,661	23,983
Weighted average fair value per share		$ 24.97	$ 37.70	$ 28.50	$ 36.90
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares authorized		2,500,000		2,500,000