Amortization Of Debt Discount And Debt Issuance Costs Incurred During Noncash Or Partial Noncash Transaction

No definition available.

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Namespace Prefix:	evh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Debt Instrument, Redemption, Call Protection Premium, Percentage

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Period Type:	instant

- Details

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- Details

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- Details

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Long-term Debt - Credit Agreement (Details) - USD ($)		3 Months Ended
Long-term Debt - Credit Agreement (Details) - USD ($)	Dec. 30, 2019	Mar. 31, 2020	Dec. 31, 2019	Dec. 31, 2016
Secured Debt \| Initial Term Loan Facility
Debt Instrument [Line Items]
Face amount	$ 75,000,000.0
Secured Debt \| Senior Credit Facilities
Debt Instrument [Line Items]
Interest expense		$ 2,000,000.0
Debt issuance costs	$ 4,700,000
Non-cash amortization of debt discount and debt issuance costs		600,000
Secured Debt \| Senior Credit Facilities \| Maximum
Debt Instrument [Line Items]
Term	91 days
Secured Debt \| Senior Credit Facilities \| After the Second Anniversary of the Closing of the Senior Credit Facilities but Prior to the Third Anniversary
Debt Instrument [Line Items]
Redemption, call protection premium, percentage	4.00%
Secured Debt \| Senior Credit Facilities \| After the Third Anniversary of the Closing of the Senior Credit Facilities but Prior to the Fourth Anniversary
Debt Instrument [Line Items]
Redemption, call protection premium, percentage	3.00%
Secured Debt \| Senior Credit Facilities \| After the Fourth Anniversary of the Closing of the Senior Credit Facilities but Prior to the Fifth Anniversary
Debt Instrument [Line Items]
Redemption, call protection premium, percentage	2.00%
Secured Debt \| Senior Credit Facilities \| Eurodollar
Debt Instrument [Line Items]
Basis spread on variable rate	8.00%
Secured Debt \| Senior Credit Facilities \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	7.00%
Senior Notes \| Convertible Senior Notes due 2021
Debt Instrument [Line Items]
Face amount		125,000,000	$ 125,000,000	$ 125,000,000.0
Interest rate	2.00%			2.00%
Interest expense		$ 600,000
Debt issuance costs				$ 4,600,000
DDTL Facility \| Line of Credit \| Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 50,000,000.0
Commitment fee percentage	1.00%