Commitments and Contingencies - Narrative (Details) $ in Millions	Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items]
Parental guaranteed obligations	$ 22.3
Minimum
Loss Contingencies [Line Items]
Operating lease term	1 year
Aggregate medical claims for umbrella insurance coverage per calendar year	$ 6.0
Maximum
Loss Contingencies [Line Items]
Operating lease term	7 years

This line item represents the amount of aggregate medical claims for umbrella insurance coverage.

No definition available.

Name:	ae_AggregateMedicalClaimsForUmbrellaInsuranceCoverage
Namespace Prefix:	ae_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

No definition available.

+ Details

Name:	ae_GuaranteedObligations
Namespace Prefix:	ae_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Period Type:	duration

- Details

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- Details

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