Commitments and Contingencies Future minimum lease payments for financing transactions (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013
Leases [Abstract]
Minimum Lease Payments, Capital Leases, Next Twelve Months	$ 3,411
Minimum Lease Payments, Capital Leases, within Two Years	3,486
Minimum Lease Payments, Capital Leases, within Three Years	3,604
Minimum Lease Payments, Capital Leases, within Four Years	3,735
Minimum Lease Payments, Capital Leases, within Five Years	4,196
Minimum Lease Payments, Capital Leases, Thereafter	651
Minimum Lease Payments, Capital Leases	19,083
Interest Portion of Minimum Lease Payments, Sale Leaseback Transactions	(2,962)
Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments	16,121
Other Long-term Debt for building, Current	2,459
Other Long-term Debt for building, Noncurrent	$ 13,662

Other Long-term Debt, Current, Building leases

No definition available.

Name:	elon_OtherLongTermDebtCurrentBuildingLeases
Namespace Prefix:	elon_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Other long term debt, noncurrent, building leases

+ References

No definition available.

+ Details

Name:	elon_OtherLongTermDebtNoncurrentBuildingLeases
Namespace Prefix:	elon_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

+ Details

Name:	us-gaap_CapitalLeasesFutureMinimumPaymentsPresentValueOfNetMinimumPayments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount necessary to reduce minimum lease payments to present value for sale-leaseback transactions accounted for using the deposit method or as a financing.

+ References

+ Details

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

- Details

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

- Definition

Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6456377&loc=d3e50824-112756

+ Details

Name:	us-gaap_MinimumLeasePaymentsSaleLeasebackTransactions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsThereafter
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsWithinFiveYears
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsWithinFourYears
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsWithinOneYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsWithinThreeYears
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of minimum lease payments for sale-leaseback transactions accounted for using the deposit method or as a financing due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

Name:	us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsWithinTwoYears
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant