Net Income (Loss) per Common Share - Basic and Diluted (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Earnings Per Share [Abstract]
Income available to common shareholders	$ 2,590	$ 1,468	$ 6,154	$ 3,964
Weighted average common shares outstanding (shares)	123,544	123,016	123,519	122,654
Dilutive effect of equity incentive plans	$ 1,935	$ 34	$ (488)	$ 1
Weighted average common shares outstanding, assuming dilution (shares)	125,479	123,050	123,031	122,655
Basic earnings per common share (usd per share)	$ 0.02	$ 0.01	$ 0.05	$ 0.03
Diluted earnings per common share (usd per share)	$ 0.02	$ 0.01	$ 0.05	$ 0.03

Amount of increase (decrease) to net income used for calculating diluted earnings per share (EPS), resulting from the assumed exercise of stock options or restrictive stock units (RSUs).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (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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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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