Investment in Securities, Maturities of Investment Securities (Details) - USD ($)
$ in Thousands |
12 Months Ended |
Dec. 31, 2016 |
Dec. 31, 2015 |
| Securities Available for Sale, Amortized Cost [Abstract] |
|
|
| Due in one year or less, Amortized Cost |
$ 11,010
|
|
| Due after one year through five, Amortized Cost |
343,904
|
|
| Due after five year through ten years, Amortized Cost |
144,748
|
|
| Due after ten years, Amortized Cost |
558,888
|
|
| Residential mortgage-backed securities, Amortized Cost |
684
|
|
| Collateralized mortgage obligations, Amortized Cost |
45,069
|
|
| Amortized Cost |
1,104,303
|
$ 1,088,258
|
| Securities available for sale, Estimated Fair Value [Abstract] |
|
|
| Due in one year or less, Estimated Fair Value |
11,116
|
|
| Due after one year through five, Estimated Fair Value |
347,140
|
|
| Due after five year through ten years, Estimated Fair Value |
152,225
|
|
| Due after ten years, Estimated Fair Value |
595,559
|
|
| Residential mortgage-backed securities, Estimated Fair Value |
718
|
|
| Collateralized mortgage obligations, Estimated Fair Value |
44,885
|
|
| Total, estimated fair value |
1,151,643
|
1,133,645
|
| Securities held to maturity, Amortized Cost [Abstract] |
|
|
| Due in one year or less, Amortized Cost |
2,026
|
|
| Due after ten years, Amortized Cost |
619
|
|
| Residential mortgage-backed securities, Amortized Cost |
191
|
|
| Amortized Cost |
2,836
|
2,929
|
| Securities held to maturity, Estimated Fair Value [Abstract] |
|
|
| Due in one year or less, Estimated Fair Value |
2,026
|
|
| Due after ten years, Estimated Fair Value |
777
|
|
| Residential mortgage-backed securities, Estimated Fair Value |
209
|
|
| Total, Estimated fair value |
3,012
|
3,124
|
| Amortized cost of deposited with commissioner of insurance code |
5,358
|
5,136
|
| Fair value of deposited with commissioner of insurance code |
$ 5,788
|
$ 5,276
|