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Pension Plans and Other Postretirement Benefits (Details-7) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Expected Cash Flows |  |  |
Expected employer contributions, 2016 | $ 10,000 |  |
Expected employer contributions, 2017 | 0 |  |
Cash contributions to pension and other postretirement plans | 13,676 | $ 3,321 | $ 34,765
Pension Benefits [Member] |  |  |
Benefit Payments |  |  |
Defined benefit plan expected future benefit payments, 2016 | 12,489 |  |
Defined benefit plan expected future benefit payments, 2017 | 13,320 |  |
Defined benefit plan expected future benefit payments, 2018 | 14,506 |  |
Defined benefit plan expected future benefit payments, 2019 | 15,456 |  |
Defined benefit plan expected future benefit payments, 2020 | 16,381 |  |
Defined benefit plan expected future benefit payments, 2021-2025 | 95,167 |  |
Postretirement Benefits [Member] |  |  |
Benefit Payments |  |  |
Defined benefit plan expected future benefit payments, 2016 | 2,892 |  |
Defined benefit plan expected future benefit payments, 2017 | 3,232 |  |
Defined benefit plan expected future benefit payments, 2018 | 3,674 |  |
Defined benefit plan expected future benefit payments, 2019 | 4,157 |  |
Defined benefit plan expected future benefit payments, 2020 | 4,585 |  |
Defined benefit plan expected future benefit payments, 2021-2025 | 28,243 |  |
Gross Postretirement Benefits [Member] |  |  |
Benefit Payments |  |  |
Defined benefit plan expected future benefit payments, 2016 | 3,119 |  |
Defined benefit plan expected future benefit payments, 2017 | 3,481 |  |
Defined benefit plan expected future benefit payments, 2018 | 3,947 |  |
Defined benefit plan expected future benefit payments, 2019 | 4,453 |  |
Defined benefit plan expected future benefit payments, 2020 | 4,910 |  |
Defined benefit plan expected future benefit payments, 2021-2025 | 30,364 |  |
Expected Medicare Part D Subsidy [Member] |  |  |
Benefit Payments |  |  |
Defined benefit plan expected future benefit payments, 2016 | (227) |  |
Defined benefit plan expected future benefit payments, 2017 | (249) |  |
Defined benefit plan expected future benefit payments, 2018 | (273) |  |
Defined benefit plan expected future benefit payments, 2019 | (296) |  |
Defined benefit plan expected future benefit payments, 2020 | (325) |  |
Defined benefit plan expected future benefit payments, 2021-2025 | $ (2,121) |  |

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- Definition Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + 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 (f) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + 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 (f) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + 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 (f) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + 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 (f) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + 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 (f) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + 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 (f) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. + 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 (g) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition The amount of cash or cash equivalents contributed during the reporting period by the entity to fund its pension plans and its non-pension postretirement benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3536-108585 + Details
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