XML 51 R38.htm IDEA: XBRL DOCUMENT v3.4.0.3

Derivative Instruments Schedule of Futures (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Derivative, Fair Value, Net	$ (16,649)	$ (2,542)
Futures [Member] | Short [Member]
Derivative [Line Items]
Derivative notional	(18,000)	(21,000)
Derivative, Fair Value, Net	$ (4)	$ 18
Derivative, Average Remaining Maturity	10 months 6 days	11 months 21 days
Futures [Member] | Short [Member] | Year 2016 [Member]
Derivative [Line Items]
Derivative notional	$ (9,000)	$ (12,000)
Derivative, Fair Value, Net	$ 1	$ 10
Derivative, Average Remaining Maturity	5 months 20 days	7 months 4 days
Futures [Member] | Short [Member] | Year 2017 [Member]
Derivative [Line Items]
Derivative notional	$ (9,000)	$ (9,000)
Derivative, Fair Value, Net	$ (5)	$ 8
Derivative, Average Remaining Maturity	14 months 23 days	17 months 24 days

X

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

Name:	invest_DerivativeNotionalAmount
Namespace Prefix:	invest_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Average remaining period until maturity of the derivative contract, 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_DerivativeAverageRemainingMaturity1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13433-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13495-108611

+ Details

Name:	us-gaap_DerivativeFairValueOfDerivativeNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- 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

X

- Details

Name:	us-gaap_DerivativeByNatureAxis=us-gaap_FutureMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

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

X

- Details

Name:	earn_RemainingMaturityAxis=earn_Year2016Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	earn_RemainingMaturityAxis=earn_Year2017Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: