v2.4.0.8

Fair Value Measurements - Estimate of the Fair Value of Financial Instruments Not Recorded at Fair Value on Balance Sheet (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Financial Assets:
State tax credits held for sale	$ 20,139	$ 23,020
Fair Value, Level 1
Financial Assets:
Portfolio loans, net	0	0
State tax credits held for sale	0	0
Financial Liabilities:
Deposits	1,825,274	2,079,141
Subordinated debentures	0	0
Federal Home Loan Bank advances	0	0
Other borrowings	0	0
Fair Value, Level 2
Financial Assets:
Portfolio loans, net	0	0
State tax credits held for sale	0	0
Financial Liabilities:
Deposits	0	0
Subordinated debentures	40,474	65,840
Federal Home Loan Bank advances	126,234	89,301
Other borrowings	178,228	245,224
Fair Value, Level 3
Financial Assets:
Portfolio loans, net	2,229,411	2,266,834
State tax credits held for sale	40,798	43,802
Financial Liabilities:
Deposits	628,696	589,972
Subordinated debentures	0	0
Federal Home Loan Bank advances	0	0
Other borrowings	0	0
Estimated fair value
Financial Assets:
Portfolio loans, net	2,229,411	2,266,834
State tax credits held for sale	40,798	43,802
Financial Liabilities:
Deposits	2,453,970	2,669,113
Subordinated debentures	40,474	65,840
Federal Home Loan Bank advances	126,234	89,301
Other borrowings	$ 178,228	$ 245,224

X

- Definition

Loans And Leases Receivable Net Reported Amount Fair Value Disclosure

+ References

No definition available.

+ Details

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

X

- Definition

Other Borrowings Fair Value Disclosure

+ References

No definition available.

+ Details

Name:	efsc_OtherBorrowingsFairValueDisclosure
Namespace Prefix:	efsc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

State Tax Credits Held For Sale, Fair Value Disclosure

+ References

No definition available.

+ Details

Name:	efsc_StateTaxCreditsHeldForSaleFairValueDisclosure
Namespace Prefix:	efsc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

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

X

- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

+ Details

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

X

- Definition

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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X

- Definition

Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

+ 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 210.9-03.13(3)(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
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- Details

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