Summary of Significant Accounting Policies - EPS (Details) - USD ($)	3 Months Ended						12 Months Ended
	Dec. 31, 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
Net (loss) earnings per common share - basic and diluted:
Net (loss) earnings							$ (1,068,000)	$ 786,000	$ 1,873,000
Allocation to nonvested restricted stock awards								20,000	44,000
Net (loss) earnings available to common stockholders							$ (1,068,000)	$ 766,000	$ 1,829,000
Weighted-average shares outstanding - basic and diluted							32,321,000	32,201,000	32,085,000
Net (loss) earnings per common share - basic and diluted	$ (0.02)	$ (0.01)	$ (0.01)	$ 0.02	$ 0.02	$ (0.01)	$ (0.03)	$ 0.02	$ 0.06
Anti-dilutive securities not included in the computation of diluted EPS (in shares)							0	0	0
Dividends paid							$ 0	$ 0	$ 0
Nonvested restricted stock
Accounting for stock-based compensation
Stock-based compensation expense							295,000	326,000	375,000
Income tax benefit (expense) related to vesting of restricted stock awards							$ 48,000	$ 14,000	$ (20,000)