Oil and Gas Reserve Data (Unaudited) - Summary of Proved Developed and Undeveloped Reserves (Details)	Mar. 31, 2018 MBbls bbl Mcf	Mar. 31, 2017 MBbls bbl Mcf	Mar. 31, 2016 bbl Mcf
Proved Developed Reserves \| MBbls	2,111,000
Proved Undeveloped Reserves \| MBbls	1,036,503	2,153,248
Oil [Member]
Proved Developed Reserves \| bbl	390,740	399,880	350,180
Proved Undeveloped Reserves \| bbl	805,980	1,724,420	734,170
Natural Gas [Member]
Proved Developed Reserves \| Mcf	4,103,390	4,107,950	4,406,060
Proved Undeveloped Reserves \| Mcf	1,383,120	2,572,960	1,395,220

Net quantities of an enterprise's interests in proved developed reserves of either crude oil (including condensate and natural gas liquids), natural gas, synthetic oil and gas, or other nonrenewable natural resource that is intended to be upgraded into synthetic oil and gas as of the beginning and the end of the year. "Net" quantities of reserves include those relating to the enterprise's operating and nonoperating interests in properties. Quantities of reserves relating to royalty interests owned are included in "net" quantities if the necessary information is available to the enterprise. "Net" quantities does not include reserves relating to interests of others in properties owned by the enterprise. The unit of measure for reserve quantities is defined as "barrels" for oil and synthetic oil reserves or "cubic feet" or "cubic meters" for natural gas and synthetic gas reserves.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Form 20-F
-Section Item 18
-Subsection Instruction 2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 235
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68064819&loc=d3e61797-109447

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Data Type:	num:volumeItemType
Balance Type:	na
Period Type:	instant