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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items] |  |  |
Accumulated benefit obligation | $ 58,000 | $ 53,500 |
Number of consecutive years used for compensation calculation | 5 years |  |
Investment strategy, percentage in long-term growth | 97.00% |  |
Investment strategy, percentage in near-term benefit payments | 3.00% |  |
Maximum percentage of securities purchasing allowed of the portfolio at any time | 5.00% |  |
Maximum market value purchase percentage allowed of any one issuer | 8.00% |  |
Expense included in salaries and employee benefits |  | 1,300 | $ 1,100
Postretirement Benefit Plan, Accrued liabilities | $ 149 | $ 107 |
Estimated future net loss for the plan that will be amortized from accumulated other comprehensive income | 1,200 |  |
Estimated future prior service credit for the plan that will be amortized from accumulated other comprehensive income | $ 51 |  |
Maximum percent of participant's contribution match | 4.50% |  |
Securities Less Than Aquality [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Maximum percentage of securities purchasing allowed of the portfolio at any time | 13.00% |  |
Commercial Mortgage Back Securities And Assets Backed Securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Maximum percentage of securities purchasing allowed of the portfolio at any time | 10.00% |  |
Portfolio Concentration Commingled Trust Fund1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of Plan Assets | 14.00% | 11.00% |
Portfolio Concentration Commingled Trust Fund2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of Plan Assets | 6.00% | 7.00% |
Portfolio Concentration Exchange Traded Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of Plan Assets |  | 7.00% |
Portfolio Concentration Short Term Investment Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage of Plan Assets | 6.00% | 5.00% |
Investment Firm One [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Portfolio management, controlled percentage | 58.00% | 58.00% |
Investment Firm Two [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Portfolio management, controlled percentage | 38.00% | 38.00% |
Defined Benefit Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Portfolio management, controlled percentage | 4.00% | 4.00% |
First 3% Of Participant's Contribution [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage employer matches of the employee's percentage contribution matched | 100.00% |  |
Percentage for which the employer contributes a matching contribution | 3.00% |  |
Next 3% Of Participant's Contribution [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Percentage employer matches of the employee's percentage contribution matched | 50.00% |  |
Percentage for which the employer contributes a matching contribution | 3.00% |  |
SERP [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Unfunded pension liability | $ 2,100 | $ 2,300 |
Pension expense | $ 88 | $ 408 | $ 295

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- Definition This represents the entire liability recognized in the balance sheet that is associated with the defined benefit pension plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=21915240&loc=d3e1703-114919 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2410-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2417-114920 + Details
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- Definition For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accumulated Benefit Obligation -URI http://asc.fasb.org/extlink&oid=6503844 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition This represents the entire liability recognized in the balance sheet that is associated with the defined benefit pension plans and other postretirement and postemployment benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=21915240&loc=d3e1703-114919 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2410-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2417-114920 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.15) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 + Details
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- Definition The amount of pension benefit costs recognized during the period for (1) defined benefit plans and (2) defined contribution plans. For defined benefit plans, pension expense includes the following components: service cost, interest cost, expected return on plan assets, gain (loss) on plan assets, prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments. For defined contribution plans, the pension expense generally equals the firm's contribution to employees' accounts (if the firm contributes) during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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