Earnings Per Common Share (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income per share calculations for basic and diluted methods
Net income available to common stockholders (in dollars)	$ 7,579	$ 7,705
Shares:
Weighted average common shares outstanding	86,957,000	86,866,000
Dilutive effect of outstanding options, warrants and restricted stock units as determined by the application of the treasury stock method (in shares)	551,000	365,000
Weighted average common shares outstanding, as adjusted for diluted earnings per share calculation	87,508,000	87,231,000
Basic earnings per common share (in dollars per share)	$ 0.09us-gaap_EarningsPerShareBasic	$ 0.09us-gaap_EarningsPerShareBasic
Diluted earnings per common share (in dollars per share)	$ 0.09us-gaap_EarningsPerShareDiluted	$ 0.09us-gaap_EarningsPerShareDiluted
Stock options
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)	261,306	482,430
Warrants
Anti-dilutive securities excluded from the calculation of common stock equivalents
Number of anti-dilutive securities (in shares)	573,833	573,833

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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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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