Pension Plans and Other Postretirement Benefits (Details-6) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	$ 327,500	$ 315,000
Real Estate [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	23,480	19,628
Insurance Continuance Fund [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	1,518	1,428
Fixed Rate Fund [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	4,446
Level 3 [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at end of year	29,444	21,056
Level 3 [Member] \| Real Estate [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	19,628	17,141
Actual return on plan assets still held	1,561	1,565
Purchases, sales, and settlements	2,291	922
Transfers in and/or out of Level 3	0	0
Fair value of plan assets at end of year	23,480	19,628
Level 3 [Member] \| Insurance Continuance Fund [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	1,428	1,466
Actual return on plan assets still held	44	42
Purchases, sales, and settlements	46	(80)
Transfers in and/or out of Level 3	0	0
Fair value of plan assets at end of year	1,518	1,428
Level 3 [Member] \| Fixed Rate Fund [Member]
Change in plan assets [Roll Forward]
Fair value of plan assets at beginning of year	0	0
Actual return on plan assets still held	54	0
Purchases, sales, and settlements	4,392	0
Transfers in and/or out of Level 3	0	0
Fair value of plan assets at end of year	$ 4,446	$ 0

Actual return on plan assets, separately identifying the amount related to assets still held at the reporting date.

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=35743120&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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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

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-SubTopic 20

-Section 50

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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

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- Definition

Transfers in and out of Level 3. For example, transfers due to changes in the observability of significant inputs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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