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Pension Plans and Other Postretirement Benefits (Details Textual) - USD ($) | 2 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2014 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Sep. 30, 2016 | Dec. 31, 2006
Pension Plans and Other Postretirement Benefits Additional Textual [Abstract] |  |  |  |  |  |
Minimum Years of Service Required |  |  |  | 1 year |  |
Pension Expense |  | $ 8,527,000 | $ 8,899,000 | $ 11,850,000 |  |
Health Reimbursement Account Balance |  | 1,652,000 |  |  |  | $ 7,310,000
Reduction in Expenses Due to Change in Plan |  |  |  | 2,980,000 |  |
Health Reimbursement Accounts Funding | $ 252,000 | $ 218,000 | $ 523,000 | $ 252,000 |  |
Debt Securities [Member] |  |  |  |  |  |
Pension Plans and Other Postretirement Benefits Additional Textual [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Target Allocation Percentage |  | 50% fixed income funds |  |  |  |
Equity Securities [Member] |  |  |  |  |  |
Pension Plans and Other Postretirement Benefits Additional Textual [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Target Allocation Percentage |  | 50% equity |  |  |  |
Qualified Defined Contribution Plan [Member] |  |  |  |  |  |
Pension Plans and Other Postretirement Benefits Additional Textual [Abstract] |  |  |  |  |  |
Employer Contribution as Percentage of Eligible Compensation |  |  |  | 5.00% |  |
Minimum Years of Service Required |  |  |  | 3 years |  |
Employee Vesting Percentage |  |  |  | 100.00% |  |
401 K Plan [Member] |  |  |  |  |  |
Pension Plans and Other Postretirement Benefits Additional Textual [Abstract] |  |  |  |  |  |
Employee Vesting Percentage |  | 100.00% |  |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay |  | 3.00% |  |  |  |
Deferred Compensation Arrangement with Individual, Requisite Service Period |  | 5 years |  |  |  |
Defined Benefit Plan [Member] |  |  |  |  |  |
Pension Plans and Other Postretirement Benefits Additional Textual [Abstract] |  |  |  |  |  |
Defined Benefit Plan Termination Benefits Terminated Participants Minimum Accrued Lump Sum Values | 100,000 |  |  |  |  |
Deferred Compensation Arrangement with Individual, Cash Award Granted, Amount | 4,200,000 |  |  | $ 4,200,000 | $ 1,400 |
Deferred Compensation Arrangement with Individual, Compensation Expense | $ 1,600,000 |  |  |  |  |
Defined Benefit Plan, Future Amortization of Gain (Loss) |  | $ 389,000 |  |  |  |
Supplemental Defined Benefit Plans [Member] |  |  |  |  |  |
Pension Plans and Other Postretirement Benefits Additional Textual [Abstract] |  |  |  |  |  |
Defined Benefit Plan, Future Amortization of Gain (Loss) |  | $ 258,000 |  |  |  |

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- Definition Represents Defined Benefit Plan Termination Benefits, Terminated Participants Minimum Accrued Lump Sum Values. + References No definition available. + Details
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- Definition Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 710 -SubTopic 10 -Section 55 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6409961&loc=d3e20487-108367 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Description of target allocation percentages, or range of percentages, considering the major categories of plan assets as of the latest statement of financial position presented (on a weighted-average basis for employers with more than one plan) that are pertinent to an understanding of the plan investment policies and strategies. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 + 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=66902209&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=65897934&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=65897934&loc=d3e1928-114920 + Details
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