Capital Stock (Narrative) (Details)		3 Months Ended	6 Months Ended
	Mar. 17, 2017 $ / shares	Jun. 30, 2018 $ / shares shares	Jun. 30, 2018 $ / shares shares	Dec. 31, 2017 $ / shares shares	Mar. 16, 2017 $ / shares
Capital Stock [Line Items]
Common stock, New shares issued		0
Common stock, par value | $ / shares		$ 0.001	$ 0.001	$ 0.001
Preferred stock, shares authorized		25,000,000	25,000,000	25,000,000
Dividends conversion ratio			0.001
Exercise price | $ / shares					$ 1.10
Rights Plan [Member]
Capital Stock [Line Items]
Number of preferred share purchase right for each outstanding share of its common stock to shareholder | $ / shares	$ 1
Common stock, Threshold for exercise of rights percentage	4.95%
Rights [Member]
Capital Stock [Line Items]
Date declared			Mar. 17, 2017
Date to be paid			Mar. 27, 2017
Date of record			Mar. 16, 2017
Series A Preferred Stock [Member]
Capital Stock [Line Items]
Preferred stock, shares authorized		10,000	10,000	10,000
Preferred stock, par value | $ / shares		$ 0.0001	$ 0.0001	$ 0.0001
Preferred stock, shares issued		0	0	0
Series A Preferred Stock [Member] | Rights Plan [Member]
Capital Stock [Line Items]
Preferred stock, shares issued		0	0