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Pension Plans and Other Postretirement Benefits (Details-6) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014
Change in plan assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | $ 327,500 |
Fair value of plan assets at end of year | 330,886 | $ 327,500
Real Estate [Member] |  |
Change in plan assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 23,480 |
Fair value of plan assets at end of year | 27,231 | 23,480
Insurance Continuance Fund [Member] |  |
Change in plan assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 1,518 |
Fair value of plan assets at end of year | 1,518 | 1,518
Fixed Rate Fund [Member] |  |
Change in plan assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 4,446 |
Fair value of plan assets at end of year | 4,208 | 4,446
Level 3 [Member] |  |
Change in plan assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 29,444 |
Fair value of plan assets at end of year | 32,957 | 29,444
Level 3 [Member] | Real Estate [Member] |  |
Change in plan assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 23,480 | 19,628
Actual return on plan assets still held | 2,749 | 1,561
Purchases, sales, and settlements | 1,002 | 2,291
Transfers in and/or out of Level 3 | 0 | 0
Fair value of plan assets at end of year | 27,231 | 23,480
Level 3 [Member] | Insurance Continuance Fund [Member] |  |
Change in plan assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 1,518 | 1,428
Actual return on plan assets still held | 46 | 44
Purchases, sales, and settlements | (46) | 46
Transfers in and/or out of Level 3 | 0 | 0
Fair value of plan assets at end of year | 1,518 | 1,518
Level 3 [Member] | Fixed Rate Fund [Member] |  |
Change in plan assets [Roll Forward] |  |
Fair value of plan assets at beginning of year | 4,446 | 0
Actual return on plan assets still held | 103 | 54
Purchases, sales, and settlements | (341) | 4,392
Transfers in and/or out of Level 3 | 0 | 0
Fair value of plan assets at end of year | $ 4,208 | $ 4,446

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- Definition Actual return on plan assets, separately identifying the amount related to assets still held at the reporting 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 (d)(iv)(02)(A) -URI http://asc.fasb.org/extlink&oid=58740216&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)(iv)(02)(A) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=49178875&loc=d3e12355-114930 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Definition Amount of increase (decrease) in plan assets from purchases, sales and settlement of plan obligations. + 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)(iv)(02)(B) -URI http://asc.fasb.org/extlink&oid=58740216&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)(iv)(02)(B) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 + Details
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