Fair value of financial instruments (Equity Investments) (Details) $ in Thousands	3 Months Ended
Sep. 30, 2018 USD ($)
Equity Securities [Roll Forward]
Carrying value (cost basis), June 30, 2018	$ 708
Upward adjustments	1,259
Downward adjustments (including impairment)	0
Carrying value, September 30, 2018	1,967
Equity securities without readily determinable fair value, amount	$ 1,500

Equity Securities, FV-NI and without Readily Determinable Fair Value, Amount Measured Based On Observable Inputs

No definition available.

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- Definition

Equity Securities [Roll Forward]

+ References

No definition available.

+ Details

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI) and investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

+ Details

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- Definition

Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84241550&loc=SL75117546-209714

+ Details

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- Definition

Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

+ Details

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