Impairment, restructuring and other charges (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Jun. 30, 2015
Impairment, Restructuring and Other Charges [Line Items]
Impairment of fixed assets			$ 5,888
Impairment of minority interest investment			2,853
Total impairment charges			8,741
Employee termination costs	$ 2,158	$ 1,606	2,700	$ 1,930
Charges related to government contract issues	496	1,848	496	3,614
Charges related to class action litigation				625
Legal settlement and related costs	125		1,843
Acquisition costs	1,438		1,438
Other	320	166	416	256
Total impairment, restructuring and other charges	4,537	$ 3,620	15,634	$ 6,425
Other accrued expenses
Impairment, Restructuring and Other Charges [Line Items]
Accrued restructuring and other charges	$ 3,400		$ 3,400		$ 3,400

Nonrecurring charges related to class action litigation.

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Nonrecurring charges related to government contract issues.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

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Amount of other expense (income) that is infrequent in occurrence or unusual in nature.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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The aggregate amount provided for estimated restructuring charges, remediation costs, and asset impairment loss during an accounting period. Generally, these items are either unusual or infrequent, but not both (in which case they would be extraordinary items).

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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