v3.19.3

Earnings Per Share - Summary of Reconciliation of Numerators and Denominators Used in Basic and Diluted Per Share Computations (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Class A Common Stock [Member]
Numerator:
Allocation of net income (loss)	$ 4,269	$ 1,006	$ 27,065	$ (14,472)
Denominator:
Weighted-average shares outstanding	23,015	22,717	22,933	22,673
Basic earnings (loss) per share	$ 0.19	$ 0.04	$ 1.18	$ (0.64)
Numerator:
Allocation of net income (loss)	$ 4,269	$ 1,006	$ 27,065	$ (14,472)
Denominator:
Number of shares used in basic computation	23,015	22,717	22,933	22,673
Weighted-average shares effect of dilutive securities:
Director and employee stock options	277	178	183
Number of shares used in diluted computation	23,292	22,895	23,116	22,673
Diluted earnings (loss) per share	$ 0.18	$ 0.04	$ 1.17	$ (0.64)
Class B Common Stock [Member]
Numerator:
Allocation of net income (loss)	$ 917	$ 200	$ 5,933	$ (3,290)
Denominator:
Weighted-average shares outstanding	5,577	5,577	5,577	5,577
Basic earnings (loss) per share	$ 0.16	$ 0.04	$ 1.06	$ (0.59)
Numerator:
Allocation of net income (loss)	$ 917	$ 200	$ 5,933	$ (3,290)
Denominator:
Number of shares used in basic computation	5,577	5,577	5,577	5,577
Weighted-average shares effect of dilutive securities:
Number of shares used in diluted computation	5,577	5,577	5,577	5,577
Diluted earnings (loss) per share	$ 0.16	$ 0.04	$ 1.06	$ (0.59)

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- Definition

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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