Related Party Transactions - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended
Dec. 11, 2020	Dec. 31, 2020	Dec. 31, 2019
Related Party Transactions [Abstract]
Significant transaction with related party		$ 0	$ 0
Underwriters option to purchase additional shares from selling stockholders	8,548,485
Proceeds from issuance of common stock	$ 0

Underwriters Option To Purchase Additional Shares From Selling Stockholders.

No definition available.

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Namespace Prefix:	ampy_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39603-107864

+ Details

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Balance Type:	debit
Period Type:	duration

- References

No definition available.

+ Details

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