Earnings per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Numerator:
Income from continuing operations	$ 4,260	$ 4,416
Income from discontinued operations	0	28
Net income	$ 4,260	$ 4,444
Denominator:
Weighted average shares of common stock outstanding	11,862	12,108
Effect of dilutive common stock equivalents	60	89
Weighted average shares of common stock outstanding	11,922	12,197
Basic earnings per share
Earnings per share from continuing operations	$ 0.36	$ 0.36
Earnings per share from discontinued operations	0	0
Earnings per share	0.36	0.36
Diluted earnings per share
Earnings per share from continuing operations	0.36	0.36
Earnings per share from discontinued operations	0	0
Earnings per share	$ 0.36	$ 0.36

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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 of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Per basic share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation.

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