Stock-Based Compensation - Changes in Stock Options (Details)	6 Months Ended
Dec. 31, 2018 USD ($) $ / shares shares
Changes in stock options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price \| $ / shares	$ 45.24
Options outstanding, June 30, 2018 \| shares	989,992
Options, Exercised \| shares	(136,405)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period \| shares	(7,000)
Options outstanding, December 31, 2018 \| shares	846,587
Options vested and expected to vest, December 31, 2018 \| shares	846,587
Options exercisable, December 31, 2018 \| shares	841,920
Weighted Average Exercise Price, Options outstanding, June 30, 2018 \| $ / shares	$ 33.08
Weighted Average Exercise Price, Exercised \| $ / shares	29.18
Weighted Average Exercise Price, Options outstanding, December 31, 2018 \| $ / shares	33.61
Weighted Average Exercise Price, Option vested and expected to vest, December 31, 2018 \| $ / shares	33.61
Weighted Average Exercise Price, Options exercisable, December 31, 2018 \| $ / shares	$ 33.68
Weighted Average Remaining Life, Options outstanding, December 31, 2018	4 years
Weighted Average Remaining Life, Options vested and expected to vest, December 31, 2018	4 years
Weighted Average Remaining Life, Options exercisable, December 31, 2018	4 years
Aggregate Intrinsic value, Options outstanding, December 31, 2018 \| $	$ 3,018,000
Aggregate Intrinsic Value, Options vested and expected to vest, December 31, 2018 \| $	3,018,000
Aggregate Intrinsic Value, Options exercisable, December 31, 2018 \| $	$ 2,960,000

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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