Debt Trust preferred debt instruments (Details) - USD ($)
|
12 Months Ended |
|
|
Dec. 31, 2015 |
Jun. 30, 2015 |
Dec. 31, 2014 |
| Debt Instrument [Line Items] |
|
|
|
| Debt Instrument, Face Amount |
|
$ 15,800,000
|
$ 13,618,000
|
| Connecticut Statutory Trust I [Member] |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Debt Instrument, Face Amount |
$ 15,000
|
|
|
| Issue date of trust |
Dec. 04, 2002
|
|
|
| Redemption date |
Dec. 04, 2032
|
|
|
| Connecticut Statutory Trust II [Member] |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Debt Instrument, Face Amount |
$ 17,500
|
|
|
| Issue date of trust |
May 15, 2003
|
|
|
| Redemption date |
May 15, 2033
|
|
|
| Connecticut Statutory Trust III [Member] |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Debt Instrument, Face Amount |
$ 20,000
|
|
|
| Issue date of trust |
Oct. 29, 2003
|
|
|
| Redemption date |
Oct. 29, 2033
|
|
|
| Delaware Statutory Trust III [Member] |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Debt Instrument, Face Amount |
$ 15,000
|
|
|
| Issue date of trust |
May 22, 2003
|
|
|
| Redemption date |
May 22, 2033
|
|
|
| Delaware Statutory Trust IV [Member] |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Debt Instrument, Face Amount |
$ 10,000
|
|
|
| Issue date of trust |
Sep. 30, 2003
|
|
|
| Redemption date |
Sep. 30, 2033
|
|
|
| Delaware Statutory Trust VI [Member] |
|
|
|
| Debt Instrument [Line Items] |
|
|
|
| Debt Instrument, Face Amount |
$ 13,000
|
|
|
| Issue date of trust |
Jan. 08, 2004
|
|
|
| Redemption date |
Jan. 08, 2034
|
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