Basis of Presentation (Details) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2017 USD ($) $ / shares shares	Mar. 31, 2016 USD ($) $ / shares shares	Mar. 31, 2017 USD ($) segment $ / shares shares	Mar. 31, 2016 USD ($) $ / shares shares	Feb. 28, 2017
Description of Business
Number of reporting segments \| segment			3
Computation of basic and diluted earnings per share
Net income for diluted earnings per share calculation \| $	$ 14,019	$ 9,343	$ 19,529	$ 20,256
Weighted average shares outstanding for basic earnings per share calculation	18,913	19,336	18,964	19,604
Dilutive effect of stock awards (in shares)	602	605	621	657
Weighted average shares outstanding for diluted earnings per share calculation	19,515	19,941	19,585	20,261
Basic earnings per share (in dollars per share) \| $ / shares	$ 0.74	$ 0.48	$ 1.03	$ 1.03
Diluted earnings per share (in dollars per share) \| $ / shares	$ 0.72	$ 0.47	$ 1.00	$ 1.00
Stock options excluded from computation due to antidilutive effect (in shares)	48	70	47	39
Convertible Senior Notes Due 2022
Per Share Computations
Interest rate (as a percentage)	1.25%		1.25%		1.25%

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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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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Net Income or Loss Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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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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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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