Net Income (Loss) per Share - Earnings Attributable to Common Shareholders and Weighted Average Common Shares Outstanding (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Continuing operations
Net Income from continuing operations	$ 4,580	$ 24,827
Less: Net income attributable to noncontrolling interests	(46)	(40)
Earnings available for diluted earnings per share	4,534	24,787
Discontinued operations
Income from discontinued operations, net of taxes	$ 0	$ 418
Denominator:
Weighted average common shares outstanding — basic	41,939	42,097
Dilutive effect of stock options, restricted stock and equity-settled awards	27	309
Total weighted average shares outstanding — diluted	41,966	42,406
Anti-dilutive awards excluded from diluted weighted average shares (in shares)	0	1,808

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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Amount after tax of income (loss) from continuing operations attributable to the parent.

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Amount after tax of income (loss) from continuing operations including portion attributable to the noncontrolling interest.

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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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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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