Employee Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Change in plan assets
Fair value of plan assets at beginning of year	$ 99,857
Company contributions	1,500
Fair value of plan assets at end of year	110,862
Pension Benefits
Change in benefit obligation
Benefit obligation at beginning of year	117,890	109,976
Service cost	0	0	0
Interest cost	4,227	4,496	4,578
Actuarial (gains) losses	(15,393)	5,560
Participant contributions	0	0
Retiree drug subsidy received	0	0
Benefits paid	(3,112)	(2,142)
Benefit obligation at end of year	103,612	117,890	109,976
Change in plan assets
Fair value of plan assets at beginning of year	99,857	87,605
Actual gains on plan assets	12,487	11,178
Company contributions	1,630	3,216
Participant contributions	0	0
Benefits paid	(3,112)	(2,142)
Fair value of plan assets at end of year	110,862	99,857	87,605
Over (under) funded status of plans at end of year	7,250	(18,033)
Postretirement Benefits
Change in benefit obligation
Benefit obligation at beginning of year	36,054	31,558
Service cost	841	752	555
Interest cost	1,366	1,319	1,285
Actuarial (gains) losses	(4,359)	2,969
Participant contributions	514	487
Retiree drug subsidy received	61	168
Benefits paid	(1,094)	(1,199)
Benefit obligation at end of year	33,383	36,054	31,558
Change in plan assets
Fair value of plan assets at beginning of year	0	0
Actual gains on plan assets	0	0
Company contributions	580	712
Participant contributions	514	487
Benefits paid	(1,094)	(1,199)
Fair value of plan assets at end of year	0	0	0
Over (under) funded status of plans at end of year	$ (33,383)	$ (36,054)

The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)

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Amount of gain (loss) from a decision to temporarily deviate from the substantive plan, or from a change in benefit obligation or plan asset value from changes in actuarial assumptions, for example, but not limited to, interest, mortality, employee turnover or salary scale.

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1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

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The increase in the fair value of plan assets from contributions made by the employer.

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Amount of the period's gross receipts received from the prescription drug subsidy, which is to be used in the roll forward of the accumulated postretirement benefit obligation of an applicable postretirement benefit plan.

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The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

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