Condensed Consolidated Statement of Stockholders' Equity (Unaudited) - 6 months ended Jun. 30, 2018 - USD ($) $ in Thousands	Common Stock [Member] Common Class A [Member]	Common Stock [Member] Common Class B [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2017	$ 171	$ 24	$ 137,242	$ 293	$ 157,471	$ 295,201
Net income					14,388	14,388
Effect of adoption of ASU 2014-09 at Jun. 30, 2018					591	591
Other comprehensive income				1,251		1,251
Stock-based employee compensation expense			1,763			1,763
Issuance of restricted shares			357			357
Balance at Jun. 30, 2018	$ 171	$ 24	$ 139,362	$ 1,544	$ 172,450	$ 313,551

Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Value of stock related to Restricted Stock Awards issued during the period, net of the stock value of such awards forfeited.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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