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Amount of the cumulative effect on retained earnings net of related income tax effect.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794

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+ References

No definition available.

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Indicates (true false) whether practical expedient was elected not to adjust consideration for effect of financing component when transfer and customer payment for product or service occurs within one year or less.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130569-203045

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Revenues (Narrative) (Details) - USD ($)		12 Months Ended
Revenues (Narrative) (Details) - USD ($)	Oct. 01, 2018	Sep. 30, 2019
Disaggregation Of Revenue [Line Items]
Revenue, practical expedient, financing component		true
Minimum [Member]
Disaggregation Of Revenue [Line Items]
New wells production statements period		30 days
Maximum [Member]
Disaggregation Of Revenue [Line Items]
New wells production statements period		90 days
Difference between Revenue Guidance in Effect before and after Topic 606 [Member] \| ASU 2014-09, Revenue from Contracts with Customers [Member]
Disaggregation Of Revenue [Line Items]
Cumulative effect on retained earnings	$ 0