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Per share increase (decrease) in Net Income (Loss) for measurement period adjustment from accounting for tax effect pursuant to Tax Cuts and Jobs Act of 2017.

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No definition available.

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Net Income (loss) for measurement period adjustment from accounting for tax effect pursuant to Tax Cuts and Jobs Act of 2017.

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No definition available.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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No definition available.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Quarterly Results (unaudited) (Details) - USD ($)		3 Months Ended								12 Months Ended
Quarterly Results (unaudited) (Details) - USD ($)	Jan. 01, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues		$ 44,377,000	$ 45,094,000	$ 43,305,000	$ 44,148,000	$ 44,241,000	$ 47,110,000	$ 46,224,000	$ 44,717,000	$ 176,924,000	$ 182,292,000	$ 182,946,000
Operating earnings (loss)		(35,000)	(7,000)	223,000	52,000	(275,000)	1,013,000	1,509,000	34,000	$ 233,000	$ 2,281,000	$ 3,875,000
Net (loss) earnings		$ (779,000)	$ (137,000)	$ 32,000	$ (184,000)	$ (291,000)	$ 520,000	$ 796,000	$ (239,000)
Net (loss) earnings per share-basic and diluted (in dollars per share)		$ (0.02)			$ (0.01)	$ (0.01)	$ 0.02	$ 0.02	$ (0.01)	$ (0.03)	$ 0.02	$ 0.06
Effect of Tax cuts and Jobs Act
Future federal income tax rates (as a percent)										34.00%	34.00%	34.00%
Increase in net loss due to TCJA 2017		$ 662,000
Increase in net loss per share due to TCJA 2017		$ 0.02
Forecast
Effect of Tax cuts and Jobs Act
Future federal income tax rates (as a percent)	21.00%