Common stock dividend rate percentage.

No definition available.

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- Definition

Earnings Per Share [Line Items]

+ References

No definition available.

+ Details

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 28A
-URI http://asc.fasb.org/extlink&oid=96947427&loc=d3e1500-109256

+ Details

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- Definition

Number of options vested.

+ References

No definition available.

+ Details

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- Definition

Description of the stock split arrangement. Also provide the retroactive effect given by a stock split that occurs after the balance date but before the release of financial statements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

+ Details

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

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Earnings Per Share Data - Additional Information (Detail)		3 Months Ended		9 Months Ended
	Jul. 11, 2016	Jun. 30, 2017 shares	Jun. 30, 2016 shares	Jun. 30, 2017 shares	Jun. 30, 2016 shares
Earnings Per Share [Line Items]
Exercisable stock options, included in the diluted earnings per share calculation		459,000	496,000	469,000	488,000
Effect of dilutive stock options		299,000	217,000	290,000	170,000
Anti-dilutive shares		0	0	0	0
Common and Class B Stock [Member]
Earnings Per Share [Line Items]
Stock split ratio	1.5
Stock dividend percentage	50.00%
Stock split ratio description				On July 11, 2016, the Company's Board of Directors approved a three-for-two split of the Company's common and Class B stock to be effected in the form of a 50% stock dividend. As a result, shareholders received one additional share of common or Class B stock for every two shares they held of the respective class of stock as of the record date.