Provision for Income Taxes - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|---|
Jun. 30, 2018 |
Dec. 31, 2017 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
Sep. 30, 2018 |
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| Corporate tax rate | 9.50% | 35.00% | 32.10% | 13.10% | 34.90% | |
| Provisional discrete tax benefit | $ 0.9 | $ 4.4 | ||||
| 2010 Non-Plan Stock Options Agreement Options [Member] | ||||||
| Employee service share-based compensation, tax benefit from compensation expense | $ 1.3 | $ 1.3 | ||||
| Scenario, Plan [Member] | ||||||
| Corporate tax rate | 21.00% | |||||
| Income tax provision based on a blended U.S. statutory tax rate | 24.50% | |||||
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- Definition Effective Income Tax Rate Reconciliation At Blended Federal Statutory Income Tax Rate No definition available.
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| X | ||||||||||
- Definition Tax Cuts and Jobs Act of 2017, change in tax rate, income tax expense (benefit). No definition available.
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| X | ||||||||||
- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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- Details
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