Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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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=29635418&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=35743120&loc=d3e1928-114920

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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=35743120&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=35743120&loc=d3e1928-114920

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- Details

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Benefit Plans Plan Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 109,415	$ 103,879
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations as a percent of toal plan assets	56.00%
Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 9,500	6,811
Actual plan asset allocations as a percent of toal plan assets	9.00%
Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 104,953	99,628	$ 91,358
Pension Plan [Member] \| Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 37,088	$ 35,034
Actual plan asset allocations as a percent of toal plan assets	35.00%	35.00%
Pension Plan [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 58,958	$ 58,286
Actual plan asset allocations as a percent of toal plan assets	56.00%	59.00%
Pension Plan [Member] \| Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 8,907	$ 6,308
Actual plan asset allocations as a percent of toal plan assets	9.00%	6.00%
Other Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 4,462	$ 4,251	$ 3,995
Other Postretirement Benefit Plan [Member] \| Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1,527	$ 1,401
Actual plan asset allocations as a percent of toal plan assets	34.00%	33.00%
Other Postretirement Benefit Plan [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 2,343	$ 2,347
Actual plan asset allocations as a percent of toal plan assets	53.00%	55.00%
Other Postretirement Benefit Plan [Member] \| Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 592	$ 503
Actual plan asset allocations as a percent of toal plan assets	13.00%	12.00%