New Accounting Pronouncements - Additional Information (Detail) - ASU 2016-09 [Member] - USD ($)	3 Months Ended	6 Months Ended
Mar. 31, 2016	Mar. 31, 2016
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Adjustments to increase (reduce) income tax provision		$ (100,000)
Adjustments to increase (decrease) net income		$ 100,000
Increase (decrease) in net income per basic and diluted share		$ 0.01
Excess tax benefit from stock-based compensation plans		$ 100,000
Maximum [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Adjustments to increase (reduce) income tax provision	$ 100,000
Adjustments to increase (decrease) net income	$ (100,000)
Increase (decrease) in net income per basic and diluted share	$ (0.01)

New accounting pronouncement or change in accounting principle effect of change on income tax provision.

No definition available.

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- Definition

New accounting pronouncement or change in accounting principle effect of change on net income of basic and diluted earnings per share.

+ References

No definition available.

+ Details

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- Definition

Amount of cash outflow for realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 20
-Section 55
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=65896087&loc=d3e11374-113907

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- Definition

Amount of the effect of a change in accounting principle on net income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22583-107794

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22499-107794

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22580-107794

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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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