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Pension Plans and Other Postretirement Benefits (Details-5) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 330,886 | $ 327,500 |
Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 300 |  |
Equity Securities [Member] | U.S. Large Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 98,949 | 99,256 |
Equity Securities [Member] | U.S. Mid Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 22,446 | 22,926 |
Equity Securities [Member] | U.S. Small Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27,561 | 29,353 |
Equity Securities [Member] | International Blend [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 55,948 | 47,650 |
Fixed Income Securities [Member] | Short-Term Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 3,388 | 3,776 |
Fixed Income Securities [Member] | High Yield Bond [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 16,225 | 15,492 |
Fixed Income Securities [Member] | Long Duration Bond [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 73,112 | 79,603 |
Real Estate [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27,231 | 23,480 |
Insurance Continuance Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,518 | 1,518 |
Fixed Rate Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 4,208 | 4,446 |
Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 300 | 0 |
Level 1 [Member] | Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 300 |  |
Level 1 [Member] | Equity Securities [Member] | U.S. Large Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 1 [Member] | Equity Securities [Member] | U.S. Mid Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 1 [Member] | Equity Securities [Member] | U.S. Small Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 1 [Member] | Equity Securities [Member] | International Blend [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 1 [Member] | Fixed Income Securities [Member] | Short-Term Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 1 [Member] | Fixed Income Securities [Member] | High Yield Bond [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 1 [Member] | Fixed Income Securities [Member] | Long Duration Bond [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 1 [Member] | Real Estate [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 1 [Member] | Insurance Continuance Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 1 [Member] | Fixed Rate Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 297,629 | 298,056 |
Level 2 [Member] | Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 |  |
Level 2 [Member] | Equity Securities [Member] | U.S. Large Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 98,949 | 99,256 |
Level 2 [Member] | Equity Securities [Member] | U.S. Mid Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 22,446 | 22,926 |
Level 2 [Member] | Equity Securities [Member] | U.S. Small Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27,561 | 29,353 |
Level 2 [Member] | Equity Securities [Member] | International Blend [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 55,948 | 47,650 |
Level 2 [Member] | Fixed Income Securities [Member] | Short-Term Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 3,388 | 3,776 |
Level 2 [Member] | Fixed Income Securities [Member] | High Yield Bond [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 16,225 | 15,492 |
Level 2 [Member] | Fixed Income Securities [Member] | Long Duration Bond [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 73,112 | 79,603 |
Level 2 [Member] | Real Estate [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 2 [Member] | Insurance Continuance Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 2 [Member] | Fixed Rate Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 32,957 | 29,444 |
Level 3 [Member] | Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 |  |
Level 3 [Member] | Equity Securities [Member] | U.S. Large Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 3 [Member] | Equity Securities [Member] | U.S. Mid Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 3 [Member] | Equity Securities [Member] | U.S. Small Cap [Memeber] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 3 [Member] | Equity Securities [Member] | International Blend [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 3 [Member] | Fixed Income Securities [Member] | Short-Term Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 3 [Member] | Fixed Income Securities [Member] | High Yield Bond [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 3 [Member] | Fixed Income Securities [Member] | Long Duration Bond [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0 | 0 |
Level 3 [Member] | Real Estate [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 27,231 | 23,480 | $ 19,628
Level 3 [Member] | Insurance Continuance Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 1,518 | 1,518 | 1,428
Level 3 [Member] | Fixed Rate Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 4,208 | $ 4,446 | $ 0

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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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