Financing Receivable Modifications Reserve

No definition available.

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Namespace Prefix:	efsc_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Financing Receivable Recorded Investment 90 Days Past Due And Still Accruing Number of Loans

+ References

No definition available.

+ Details

Name:	efsc_FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruingNumberOfLoans
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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Loans and Leases Receivable, Impaired Loans, Commitment to Lend, Reserve

+ References

No definition available.

+ Details

Name:	efsc_LoansAndLeasesReceivableImpairedLoansCommitmentToLendReserve
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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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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

+ Details

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Period Type:	duration

- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

+ Details

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

- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

+ Details

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

- Definition

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18794-111554

+ Details

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

- Definition

Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Period Type:	instant

- Details

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- Details

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- Details

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Loans - Narrative (Details)	3 Months Ended		9 Months Ended
Loans - Narrative (Details)	Sep. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($) loan	Sep. 30, 2018 USD ($) loan	Sep. 30, 2017 USD ($) loan	Dec. 31, 2017 USD ($) loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans over 90 days past due and still accruing interest \| loan					0
Unadvanced commitments on impaired loans					$ 0
Specific reserves on restructured loans	$ 2,600,000.0		$ 2,600,000.0
Restructuring Reserve	8,000,000		8,000,000
Unadvanced Commitment on Impaired Loan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Estimated losses attributable to unadvanced commitments on impaired loans	350,000		350,000		350,000
Non-Covered Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Post-Modification Outstanding Recorded Balance	$ 187,000	$ 0	$ 187,000	$ 676,000
Financing Receivable, Modifications, Number of Contracts \| loan	1	0	1	1
Restructuring Reserve	$ 820,000		$ 820,000		719,000
Financing Receivable, Gross	4,219,689,000		4,219,689,000		4,024,221,000
Non-Covered Loans \| Consumer and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restructuring Reserve	0		0		0
Financing Receivable, Gross	$ 136,025,000		$ 136,025,000		$ 137,234,000