Line Of Credit Facility, Commitment Fee Stepdown Percentage

No definition available.

Name:	esi_LineOfCreditFacilityCommitmentFeeStepdownPercentage
Namespace Prefix:	esi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Write Off Of Deferred Debt Issuance Cost and Debt Discounts

+ References

No definition available.

+ Details

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Namespace Prefix:	esi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

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

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 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_DomesticLineOfCreditMember
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- Details

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- Details

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- Details

Name:	us-gaap_VariableRateAxis=us-gaap_EurodollarMember
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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
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Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
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Debt - Credit Agreement (Details) - USD ($)			12 Months Ended
Debt - Credit Agreement (Details) - USD ($)	Nov. 26, 2019	Jan. 31, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument
Write off debt issuance cost and premium		$ 22,900,000
Debt proceeds, net of discount			$ 1,493,400,000	$ 0	$ 4,142,700,000
Repayments of Debt			$ 5,351,400,000	$ 22,500,000	$ 4,122,500,000
Domestic Line of Credit \| USD Term Loan
Debt Instrument
Debt face amount		750,000,000
Spread on variable rate (percent)	0.25%
Debt proceeds, net of discount	$ 744,000,000
Repayments of Debt	$ 744,000,000
Domestic Line of Credit \| USD Term Loan \| Base Rate
Debt Instrument
Spread on variable rate (percent)	1.00%
Domestic Line of Credit \| USD Term Loan \| Eurodollar
Debt Instrument
Spread on variable rate (percent)	2.00%
Revolving Credit Facility
Debt Instrument
Maximum borrowing capacity		$ 1,080,000,000.00
Unused capacity commitment fee (percent)		0.50%
Commitment fee stepdown percentage (percent)		0.375%
Revolving Credit Facility \| Base Rate
Debt Instrument
Spread on variable rate (percent)		1.25%
Revolving Credit Facility \| Eurodollar
Debt Instrument
Spread on variable rate (percent)		2.25%
Revolving Credit Facility \| Line of Credit
Debt Instrument
Maximum borrowing capacity		$ 330,000,000