Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5580258-113959

+ Details

Name:	us-gaap_DerivativeAssetNotionalAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Average contractual rate at which a foreign currency can be purchased or sold.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeAverageForwardExchangeRate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- 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

Name:	us-gaap_DerivativeLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeRemainingMaturity1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PositionAxis=us-gaap_ShortMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=aegn_CanadianDollarUSDMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=aegn_USDBritishPoundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=aegn_EUROBritishPoundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=aegn_ZARUSDMember
Namespace Prefix:
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Derivative Financial Instruments - Summary of Derivative Positions (Details) - 12 months ended Dec. 31, 2017	GBP (£) $ / £ € / £ ZAR / $ CAD / $	USD ($) $ / £ € / £ ZAR / $ CAD / $	ZAR $ / £ € / £ ZAR / $ CAD / $
Interest Rate Swap
Derivative [Line Items]
Notional Amount \| $		$ 231,328,125
Weighted Average Remaining Maturity In Years	2 years 10 months
Sell \| Canadian Dollar/USD
Derivative [Line Items]
Notional Amount \| $		$ 1,662,500
Weighted Average Remaining Maturity In Years	3 months
Average Exchange Rate \| CAD / $	1.26	1.26	1.26
Sell \| USD/British Pound
Derivative [Line Items]
Notional Amount \| £	£ 4,595,000
Weighted Average Remaining Maturity In Years	3 months
Average Exchange Rate \| $ / £	1.35	1.35	1.35
Sell \| EURO/British Pound
Derivative [Line Items]
Notional Amount \| £	£ 2,568,300
Weighted Average Remaining Maturity In Years	3 months
Average Exchange Rate \| € / £	0.89	0.89	0.89
Sell \| USD/South African Rand
Derivative [Line Items]
Notional Amount \| ZAR			ZAR 38,371,793
Weighted Average Remaining Maturity In Years	1 month 10 days
Average Exchange Rate \| ZAR / $	12.44	12.44	12.44