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Borrowings - Additional information (Details) | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2016 USD ($) item | Dec. 31, 2015 USD ($) | Jan. 31, 2008 USD ($)
Borrowings |  |  |
Bank owned FHLBC stock | $ 3,200,000 | $ 3,700,000 |
Total borrowings | 149,685,000 | 152,113,000 |
Securities sold under repurchase agreements |  |  |
Borrowings |  |  |
Carrying amount of securities secured | 46,600,000 | 34,100,000 |
Fair value of the pledged collateral | $ 47,600,000 | 45,400,000 |
Number of customers having secured balances exceeding specified percentage of stockholders equity | item | 1 |  |
Total borrowings | $ 46,606,000 | 34,070,000 |
Securities sold under repurchase agreements | Minimum |  |  |
Borrowings |  |  |
Threshold percentage of stockholders' equity | 10.00% |  |
FHLBC advances |  |  |
Borrowings |  |  |
Borrowings at FHLBC as percentage of total assets | 35.00% |  |
Borrowings at FHLBC as percentage of book value of certain mortgage loans | 60.00% |  |
FHLBC advance amount |  | 15,000,000 |
Bank owned FHLBC stock | $ 3,200,000 |  |
Fair value of securities collateralized | 65,400,000 |  |
Principal balance of loans collateralized | 176,400,000 |  |
Combined collateral value | 178,600,000 |  |
Amount available for additional borrowings | 142,300,000 |  |
Total borrowings |  | 15,000,000 |
Subordinated debt |  |  |
Borrowings |  |  |
Face amount | 45,000,000 |  |
Total borrowings | $ 45,000,000 | 45,000,000 |
Subordinated debt | LIBOR |  |  |
Borrowings |  |  |
Variable interest rate base | three-month LIBOR |  |
Basis points added to reference rate (as a percent) | 1.50% |  |
Notes payable and other borrowings |  |  |
Borrowings |  |  |
Total borrowings | $ 500,000 | 500,000 |
Correspondent Bank |  |  |
Borrowings |  |  |
Maximum borrowing capacity | $ 45,500,000 |  |
Senior debt facility |  |  |
Borrowings |  |  |
Maximum borrowing capacity |  |  | $ 30,500,000
Senior debt facility | LIBOR |  |  |
Borrowings |  |  |
Variable interest rate base | three-month LIBOR |  |
Basis points added to reference rate (as a percent) | 0.90% |  |
Senior debt facility | Prime rate |  |  |
Borrowings |  |  |
Variable interest rate base | prime |  |
Term debt |  |  |
Borrowings |  |  |
Maximum borrowing capacity | $ 500,000 |  |
Total borrowings | 500,000 | 500,000 |
Junior subordinated debentures |  |  |
Borrowings |  |  |
Total borrowings | $ 57,579,000 | $ 57,543,000 |

X
- Definition Represents the amount of borrowings from Federal Home Loan Bank as a percentage of book value of certain mortgage loans. + References No definition available. + Details
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- Definition Represents the amount of borrowings from Federal Home Loan Bank as a percentage of total assets. + References No definition available. + Details
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- Definition Represents the principal balance of loans pledged as collateral in support of federal home loan bank advances outstanding. + References No definition available. + Details
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- Definition Represents the fair value of securities pledged as collateral in support of federal home loan bank advances outstanding + References No definition available. + Details
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- Definition Represents the number of customers having secured balances exceeding specified percentage of stockholders equity. + References No definition available. + Details
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- Definition Represents the threshold percentage which the entity uses for disclosure about the customer holding secured balances. + References No definition available. + Details
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- 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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- Definition The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR. + References No definition available. + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 + Details
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- Definition Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of advances from the Federal Home Loan Bank (FHLB). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 + Details
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- Definition Amount of the collateral pledged in support of federal home loan bank advances outstanding. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 470 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823 + Details
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- Definition Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 325 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6478792&loc=d3e63345-112809 + Details
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- 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://www.xbrl.org/2003/role/presentationRef -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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- Definition The fair value, as of the date of each statement of financial position presented, of securities which are owned but transferred to serve as collateral for the payment of repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 + Details
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- Definition The carrying amount as of the date of the latest financial statement presented of securities which are owned but transferred to serve as collateral for repurchase agreements, and for which the transferee does not have the right by contract or custom to sell or re-pledge them to an unrelated party. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (b)(1)(i) -URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729 + Details
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