Fair Value of Financial Instruments (Narrative) (Details) $ in Thousands |
9 Months Ended | |
|---|---|---|
|
Sep. 30, 2017
USD ($)
security
|
Dec. 31, 2016
USD ($)
|
|
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||
| Amortized Cost | $ 155,419 | $ 149,561 |
| Available-for-sale Securities | $ 149,160 | 140,000 |
| Collateralized debt obligations [Member] | ||
| Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||
| Acquired Trust Preferred Securities, Number of Securities | security | 10 | |
| Amortized Cost | $ 19,719 | 27,930 |
| Available-for-sale Securities | $ 14,718 | $ 20,254 |