Changes in Accumulated Other Comprehensive Loss (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Changes in accumulated other comprehensive (loss) income
Beginning balance			$ 83,139,000
Other comprehensive income (loss)	$ (202,000)	$ 41,000	(272,000)	$ 127,000
Ending balance	75,884,000		75,884,000
Reclassifications from accumulated other comprehensive (loss) income	0	0	0	0
Accumulated Other Comprehensive Loss
Changes in accumulated other comprehensive (loss) income
Beginning balance	(302,000)	(245,000)	(232,000)	(331,000)
Ending balance	$ (504,000)	$ (204,000)	$ (504,000)	$ (204,000)

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

No definition available.

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

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

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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