Financial instruments - Cash Equivalents and Short-term Deposits (Details) - USD ($) |
Dec. 31, 2016 |
Dec. 31, 2015 |
Jun. 30, 2015 |
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| Financial instruments | |||
| Cash and cash equivalents | $ 158,779,000 | $ 194,263,000 | $ 229,046,000 |
| Short-term deposits | 22,694,000 | $ 54,620,000 | $ 55,292,000 |
| Restricted cash | $ 4,017,000 |
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- Definition Bank deposits with a term of between three and twelve months. No definition available.
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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