Securities (Details) - USD ($) $ in Thousands |
Sep. 30, 2016 |
Dec. 31, 2015 |
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Amortized Cost |
$ 1,352,845
|
$ 1,390,255
|
| Gross Unrealized Gains |
21,468
|
9,546
|
| Gross Unrealized Losses |
3,202
|
14,117
|
| Fair Value |
1,371,111
|
1,385,684
|
| Obligations of U.S. Government Sponsored Entities [Member] |
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Amortized Cost |
513,251
|
551,176
|
| Gross Unrealized Gains |
13,447
|
3,512
|
| Gross Unrealized Losses |
2
|
1,795
|
| Fair Value |
526,696
|
552,893
|
| Obligations of U.S. States and Political Subdivisions [Member] |
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Amortized Cost |
83,596
|
83,981
|
| Gross Unrealized Gains |
1,098
|
898
|
| Gross Unrealized Losses |
13
|
153
|
| Fair Value |
84,681
|
84,726
|
| Residential Mortgage-Backed Securities U.S. Government Agencies [Member] |
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Amortized Cost |
160,464
|
94,459
|
| Gross Unrealized Gains |
1,721
|
1,535
|
| Gross Unrealized Losses |
436
|
1,316
|
| Fair Value |
161,749
|
94,678
|
| Residential Mortgage-Backed Securities U.S. Government Sponsored Entities [Member] |
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Amortized Cost |
591,908
|
656,947
|
| Gross Unrealized Gains |
5,202
|
3,599
|
| Gross Unrealized Losses |
2,357
|
10,449
|
| Fair Value |
594,753
|
650,097
|
| Residential Mortgage-Backed Securities Non-U.S. Government Agencies or Sponsored Entities [Member] |
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Amortized Cost |
126
|
192
|
| Gross Unrealized Gains |
0
|
2
|
| Gross Unrealized Losses |
0
|
0
|
| Fair Value |
126
|
194
|
| U.S. corporate Debt Securities [Member] |
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Amortized Cost |
2,500
|
2,500
|
| Gross Unrealized Gains |
0
|
0
|
| Gross Unrealized Losses |
338
|
338
|
| Fair Value |
2,162
|
2,162
|
| Total debt securities [Member] |
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Amortized Cost |
1,351,845
|
1,389,255
|
| Gross Unrealized Gains |
21,468
|
9,546
|
| Gross Unrealized Losses |
3,146
|
14,051
|
| Fair Value |
1,370,167
|
1,384,750
|
| Equity Securities [Member] |
|
|
| Schedule of Available-for-sale Securities [Line Items] |
|
|
| Amortized Cost |
1,000
|
1,000
|
| Gross Unrealized Gains |
0
|
0
|
| Gross Unrealized Losses |
56
|
66
|
| Fair Value |
$ 944
|
$ 934
|