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Fair Value Measurements (Narratives) (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2017 | Mar. 31, 2018 | Mar. 31, 2017 | Jun. 30, 2015 | Jun. 30, 2017
Level 1 Investments |  |  |  |  |
Assets |  |  |  |  |
Unrealized holding gain on investments |  | $ 700,000 |  |  |
Level 2 Assets and Liabilities |  |  |  |  |
Assets |  |  |  |  |
Transfers of assets between Level 1 and Level 2 |  | 0 |  |  | $ 0
Transfers of Liabilities between Level 1 and Level 2 |  | 0 |  |  | 0
Long-term debt, fair value |  | $ 178,700,000 |  |  | $ 93,700,000
Level 3 Assets and Liabilities |  |  |  |  |
Assets |  |  |  |  |
Purchases of non-marketable equity investment |  |  |  | $ 3,000,000 |
Consideration from sale of non-marketable equity investment | $ 6,800,000 |  |  |  |
Consideration from sale of non-marketable equity investment in cash | 5,400,000 |  |  |  |
Consideration from sale of non-marketable equity investment | 5,800,000 |  |  |  |
Sale of non-marketable equity investment in cash | $ 4,900,000 |  |  |  |
Shares received for sale of non-marketable equity investment | 41,685 |  |  |  |
Shares held in escrow |  | 23,252 |  |  |
Sale of non-marketable equity investment in shares market value | $ 900,000 |  |  |  |
Remaining consideration from non-marketable securities in cash | 500,000 |  |  |  |
Remaining consideration from non-marketable securities in shares | $ 500,000 |  |  |  |
Escrow period |  | 18 months |  |  |
Transfers of assets between Level 2 and Level 3 |  | $ 0 | $ 0 |  |
Transfers of liabilities between Level 2 and Level 3 |  | 0 | 0 |  |
Intangible asset and goodwill impairment |  | 0 | $ 0 |  |
Level 3 Assets and Liabilities | Common Stock |  |  |  |  |
Assets |  |  |  |  |
Consideration in shares for sale of non-marketable investment | 65,937 |  |  |  |
Consideration from sale of non-marketable equity investment in shares market value | $ 1,400,000 |  |  |  |
Level 3 Assets and Liabilities | Other Income (Expense), Net |  |  |  |  |
Assets |  |  |  |  |
Gain on investments |  | $ 3,800,000 |  |  |

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- Definition The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale. + References No definition available. + Details
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