v3.3.1.900

Subordinated Debentures (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Mar. 14, 2014 | Aug. 15, 2013 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Subordinated Borrowing [Line Items] |  |  |  |  |
Subordinated debentures |  |  | $ 56,807 | $ 56,807 |
Subordinated debentures held by trusts |  |  | $ 1,700 |  |
Conversion of subordinated debt into common stock (in shares) | 287,852 | 1,200,000 | 0 | 287,852 | 1,176,470
Additional stock issued as an inducement (in shares) |  | 25,060 |  |  |
Expense related to inducement |  |  |  |  | $ 400
EFSC Capital Trust VIII |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Trust preferred subordinated debentures | $ 5,000 | $ 20,000 |  |  |
Conversion price (usd per share) | $ 17.37 |  |  |  |
Trust preferred securities [Member] | EFSC Clayco Statutory Trust I |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Subordinated debentures |  |  | $ 3,196 | $ 3,196 |
Maturity Date |  |  | Dec. 17, 2033 |  |
Call Date |  |  | Dec. 17, 2008 |  |
Description of variable rate |  |  | 3 Month LIBOR |  |
Floating interest rate |  |  | 2.85% |  |
Trust preferred securities [Member] | EFSC Capital Trust II |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Subordinated debentures |  |  | $ 5,155 | 5,155 |
Maturity Date |  |  | Jun. 17, 2034 |  |
Call Date |  |  | Jun. 17, 2009 |  |
Description of variable rate |  |  | 3 Month LIBOR |  |
Floating interest rate |  |  | 2.65% |  |
Trust preferred securities [Member] | EFSC Statutory Trust III |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Subordinated debentures |  |  | $ 11,341 | 11,341 |
Maturity Date |  |  | Dec. 15, 2034 |  |
Call Date |  |  | Dec. 15, 2009 |  |
Description of variable rate |  |  | 3 Month LIBOR |  |
Floating interest rate |  |  | 1.97% |  |
Trust preferred securities [Member] | EFSC Clayco Statutory Trust II |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Subordinated debentures |  |  | $ 4,124 | 4,124 |
Maturity Date |  |  | Sep. 15, 2035 |  |
Call Date |  |  | Sep. 15, 2010 |  |
Description of variable rate |  |  | 3 Month LIBOR |  |
Floating interest rate |  |  | 1.83% |  |
Trust preferred securities [Member] | EFSC Statutory Trust IV |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Subordinated debentures |  |  | $ 10,310 | 10,310 |
Maturity Date |  |  | Dec. 15, 2035 |  |
Call Date |  |  | Dec. 15, 2010 |  |
Description of variable rate |  |  | 3 Month LIBOR |  |
Floating interest rate |  |  | 1.44% |  |
Trust preferred securities [Member] | EFSC Statutory Trust V |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Subordinated debentures |  |  | $ 4,124 | 4,124 |
Maturity Date |  |  | Sep. 15, 2036 |  |
Call Date |  |  | Sep. 15, 2011 |  |
Description of variable rate |  |  | 3 Month LIBOR |  |
Floating interest rate |  |  | 1.60% |  |
Trust preferred securities [Member] | EFSC Capital Trust VI |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Subordinated debentures |  |  | $ 14,433 | 14,433 |
Maturity Date |  |  | Mar. 30, 2037 |  |
Call Date |  |  | Mar. 30, 2012 |  |
Description of variable rate |  |  | 3 Month LIBOR |  |
Floating interest rate |  |  | 1.60% |  |
Trust preferred securities [Member] | EFSC Capital Trust VII |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Subordinated debentures |  |  | $ 4,124 | $ 4,124 |
Maturity Date |  |  | Dec. 15, 2037 |  |
Call Date |  |  | Dec. 15, 2012 |  |
Description of variable rate |  |  | 3 Month LIBOR |  |
Floating interest rate |  |  | 2.25% |  |
Trust preferred securities [Member] | EFSC Capital Trust VIII |  |  |  |  |
Subordinated Borrowing [Line Items] |  |  |  |  |
Fixed interest rate |  |  | 9.00% |  |

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- Definition The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Article 5 -Subsection 19, 20, 22 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 10 -Section F + Details
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