Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 166,793
Ending balance	247,343	$ 166,793
Defined Benefit Pension Items [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(2,604)	(13,257)
Unrecognized actuarial loss, net of tax of $0 in 2014 and $404 in 2015, respectively	687	(13,704)
Actuarial (gain) loss, net of tax, $0 in 2014 and $20 in 2015, respectively	(34)	230
Net current-period other comprehensive income (loss)	1,847	(13,474)
OCI, before reclassifications, net of tax		24,127
Transfer unrecognized loss for defined benefit pension plan for an unconsolidated company to other	961
Prior service credit arising during 2015, net of tax of $137	233
Ending balance	(757)	(2,604)
Actuarial gain, tax	404	0
Change in defined pension plan, tax	20	(370)
Net prior service credit, tax	137
Other [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(178)	62
Unrecognized actuarial loss, net of tax of $0 in 2014 and $404 in 2015, respectively	0
Actuarial (gain) loss, net of tax, $0 in 2014 and $20 in 2015, respectively	0	(240)
Net current-period other comprehensive income (loss)	(1,652)	(240)
OCI, before reclassifications, net of tax		0
Prior service credit arising during 2015, net of tax of $137	0
Ending balance	(1,830)	(178)
Other [Member] \| Unconsolidated Company [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
OCI, before reclassifications, net of tax	(691)
Transfer unrecognized loss for defined benefit pension plan for an unconsolidated company to other	(961)
Change in defined pension plan, tax	451
AOCI Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(2,782)	(13,195)
Unrecognized actuarial loss, net of tax of $0 in 2014 and $404 in 2015, respectively	687	(13,704)
Actuarial (gain) loss, net of tax, $0 in 2014 and $20 in 2015, respectively	(34)	(10)
Net current-period other comprehensive income (loss)	195	(13,714)
OCI, before reclassifications, net of tax		24,127
Prior service credit arising during 2015, net of tax of $137	233
Ending balance	(2,587)	$ (2,782)
AOCI Attributable to Parent [Member] \| Unconsolidated Company [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
OCI, before reclassifications, net of tax	(691)
Transfer unrecognized loss for defined benefit pension plan for an unconsolidated company to other	$ 0

Reclassification from AOCI, Unrecognized, Current Period, Net of Tax, Attributable to Parent

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Transfer to (from) AOCI, Unrecognized Loss, Current Period, Attributable to Parent

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit).

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount of tax (expense) benefit, before reclassification adjustments, related to (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement benefit plans.

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Amount of tax (expense) benefit related to cost (credit) of benefit changes attributable to plan participants' prior service resulting from a plan amendment or plan initiation that has not been recognized in net periodic benefit cost (credit).

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