Risk Management and Derivative Instruments - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
Jan. 31, 2017	Dec. 31, 2019
Derivative Instruments Gain Loss [Line Items]
Conditional rights of set-off under ISDA Master Agreement reduce the maximum amount of loss due to credit risk		$ 12.6
Commodity derivatives [Member]
Derivative Instruments Gain Loss [Line Items]
Cash settlement receipt	$ 94.1

The terms of the ISDA Agreements provide us and each of our counterparties with rights of set-off upon the occurrence of defined acts of default by either us or our counterparty to a derivative, whereby the party not in default may set-off all liabilities owed to the defaulting party against all net derivative asset receivables from the defaulting party.

No definition available.

Name:	ampy_ConcentrationRiskCreditRiskFinancialInstrumentReducedCreditExposure
Namespace Prefix:	ampy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration