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Accumulated Other Comprehensive Income (Tables) | 12 Months Ended
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Dec. 31, 2016
Accumulated Other Comprehensive Income [Abstract] |
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] | The following table shows changes in accumulated other comprehensive income (loss) by component for the years ended December 31, 2016, 2015 and 2014:
|  | Unrealized Gains and Losses on Available-for-Sale Securities (1) |  | Unrealized Gains and Losses on Pension Plan Liability (1) |  | Total (1)
Year Ended December 31, 2016 |  | (in thousands)
Beginning balance |  | $ | 386 |  |  | $ | (6,681 | ) |  | $ | (6,295 | )
Other comprehensive loss before reclassifications |  | (12,338 | ) |  | (39 | ) |  | (12,377 | )
Amounts reclassified from accumulated other comprehensive income (2) |  | (752 | ) |  | 425 |  |  | (327 | )
Net current-period other comprehensive income (loss) |  | (13,090 | ) |  | 386 |  |  | (12,704 | )
Ending balance |  | $ | (12,704 | ) |  | $ | (6,295 | ) |  | $ | (18,999 | )
Year Ended December 31, 2015 |  |  |  |  |  |
Beginning balance |  | $ | 7,462 |  |  | $ | (1,841 | ) |  | $ | 5,621 |
Other comprehensive loss before reclassifications |  | (6,069 | ) |  | (5,054 | ) |  | (11,123 | )
Amounts reclassified from accumulated other comprehensive income (2) |  | (1,007 | ) |  | 214 |  |  | (793 | )
Net current-period other comprehensive loss |  | (7,076 | ) |  | (4,840 | ) |  | (11,916 | )
Ending balance |  | $ | 386 |  |  | $ | (6,681 | ) |  | $ | (6,295 | )
Year Ended December 31, 2014 |  |  |  |  |  |
Beginning balance |  | $ | (10,108 | ) |  | $ | (1,936 | ) |  | $ | (12,044 | )
Other comprehensive income before reclassifications |  | 17,922 |  |  | — |  |  | 17,922 |
Amounts reclassified from accumulated other comprehensive income (2) |  | (352 | ) |  | 95 |  |  | (257 | )
Net current-period other comprehensive income |  | 17,570 |  |  | 95 |  |  | 17,665 |
Ending balance |  | $ | 7,462 |  |  | $ | (1,841 | ) |  | $ | 5,621 |
__________ (1) All amounts are net of tax. Amounts in parenthesis indicate debits. (2) See following table for details about these reclassifications.
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] | The following table shows details regarding the reclassifications from accumulated other comprehensive income for the years ended December 31, 2016, 2015 and 2014:
|  | Amount Reclassified from Accumulated Other Comprehensive Income |  | Affected line Item in the Consolidated Statement of Income
|  | Years Ended |  |
|  | December 31, 2016 |  | December 31, 2015 |  | December 31, 2014 |  |
|  | (in thousands) |  |
Unrealized gains and losses on available-for-sale securities |  | $ | 1,181 |  |  | $ | 1,581 |  |  | $ | 552 |  |  | Investment securities gains, net
|  | 1,181 |  |  | 1,581 |  |  | 552 |  |  | Total before tax
|  | (429 | ) |  | (574 | ) |  | (200 | ) |  | Income tax provision
|  | $ | 752 |  |  | $ | 1,007 |  |  | $ | 352 |  |  | Net of tax
Amortization of pension plan liability actuarial losses |  | $ | (668 | ) |  | $ | (336 | ) |  | $ | (149 | ) |  | Compensation and employee benefits
|  | (668 | ) |  | (336 | ) |  | (149 | ) |  | Total before tax
|  | 243 |  |  | 122 |  |  | 54 |  |  | Income tax benefit
|  | $ | (425 | ) |  | $ | (214 | ) |  | $ | (95 | ) |  | Net of tax

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- Definition Accumulated Other Comprehensive Income [Abstract] + References No definition available. + Details
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- Definition Tabular disclosure of information about items reclassified out of accumulated other comprehensive income (loss). + References No definition available. + Details
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- Definition Tabular disclosure of the components of accumulated other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669686-108580 + Details
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