Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Unrecognized tax benefits
Interest and penalties
Battle Creek [Member]
Net operating loss carryover		$ 4,951
Expiration date	Dec. 31, 2030

The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Expiration date of each operating loss carryforward included in operating loss carryforward, in CCYY-MM-DD format.

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Amount of unrecognized tax benefits.

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