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Customers with 10% (or greater) of Net Revenues - Additional information (Detail) - Entities Owned by One Global Company [Member] - Revenue [Member]	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Customer One [Member]
Percentage of concentration	24.70%
Customer One [Member] | Maximum [Member]
Percentage of concentration	1.00%
Customer Two [Member]
Percentage of concentration	22.90%
Customer Two [Member] | Maximum [Member]
Percentage of concentration	1.00%
Customer Three [Member]
Percentage of concentration	14.80%
Customer Three [Member] | Maximum [Member]
Percentage of concentration	1.00%
Customer Four [Member]
Percentage of concentration	13.70%
Customer Four [Member] | Maximum [Member]
Percentage of concentration	1.00%
Customer Five [Member]
Percentage of concentration		19.30%
Customer Six [Member]
Percentage of concentration		13.90%
Customer Seven [Member]
Percentage of concentration		12.60%
Customer Eight [Member]
Percentage of concentration		12.00%

X

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ Details

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- Details

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