Financial instruments - Derivatives - Interest rate swaps (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Receive floating
Total carrying amount (notional amount)	$ 402,049	$ 75,542
Total carrying amount (fair value)	$ 5,736	$ 545
Swap expires Jun. 29, 2018 1 [Member]
Receive floating
Fixed Interest Rate		3.315%
Notional amount		$ 19,396
Fair Value		$ 156
Swap expires Jun. 29, 2018 2 [Member]
Receive floating
Fixed Interest Rate		3.565%
Notional amount		$ 20,417
Fair Value		$ 187
Swap expires Jun. 29, 2018 3 [Member]
Receive floating
Fixed Interest Rate		2.865%
Notional amount		$ 35,729
Fair Value		$ 202
Swap expires Apr. 20, 2023 1 [Member]
Receive floating
Fixed Interest Rate	2.987%
Notional amount	$ 46,800
Fair Value	$ 699
Swap expires Apr. 20, 2023 2 [Member]
Receive floating
Fixed Interest Rate	3.012%
Notional amount	$ 46,800
Fair Value	$ 743
Swap expires Sept. 29, 2023 1 [Member]
Receive floating
Fixed Interest Rate	3.019%
Notional amount	$ 35,877
Fair Value	$ 580
Swap expires Sept. 29, 2023 2 [Member]
Receive floating
Fixed Interest Rate	3.019%
Notional amount	$ 34,963
Fair Value	$ 563
Swap expires Jul. 24, 2023 [Member]
Receive floating
Fixed Interest Rate	2.8715%
Notional amount	$ 51,400
Fair Value	$ 606
Swap expires Jun. 30, 2023 [Member]
Receive floating
Fixed Interest Rate	2.8785%
Notional amount	$ 45,807
Fair Value	$ 503
Swap expires Sept. 29, 2023 3 [Member]
Receive floating
Fixed Interest Rate	2.895%
Notional amount	$ 50,115
Fair Value	$ 653
Swap expires Sept. 30, 2023 [Member]
Receive floating
Fixed Interest Rate	2.897%
Notional amount	$ 45,986
Fair Value	$ 597
Swap expires Sept. 29, 2023 4 [Member]
Receive floating
Fixed Interest Rate	3.02%
Notional amount	$ 44,301
Fair Value	$ 793

Fair value of the assets less the liabilities of a derivative or group of derivatives.

No definition available.

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- Definition

Fixed interest rate related to the swap.

+ References

No definition available.

+ Details

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- Definition

Description of swaps which have a "receive floating" interest rate structure.

+ References

No definition available.

+ Details

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- Definition

Aggregate notional amount specified by the swap(s). Expressed as an absolute value.

+ References

No definition available.

+ Details

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- Definition

The total of the aggregate notional amount specified by the swap(s). Expressed as an absolute value.

+ References

No definition available.

+ Details

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- Definition

The amount of financial liabilities that meet either of the following conditions: (a) they meet the definition of held for trading; or (b) upon initial recognition they are designated by the entity as at fair value through profit or loss. An entity may use this designation only when permitted by paragraph 4.3.5 of IFRS 9 (embedded derivatives) or when doing so results in more relevant information, because either: (a) it eliminates or significantly reduces a measurement or recognition inconsistency (sometimes referred to as ‘an accounting mismatch’) that would otherwise arise from measuring assets or liabilities or recognising the gains and losses on them on different bases; or (b) a group of financial liabilities or financial assets and financial liabilities is managed and its performance is evaluated on a fair value basis, in accordance with a documented risk management or investment strategy, and information about the group is provided internally on that basis to the entity’s key management personnel (as defined in IAS 24). [Refer: At fair value [member]; Key management personnel of entity or parent [member]; Derivatives [member]; Financial assets; Financial liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2017-01-01
-Paragraph 8
-Subparagraph e
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=7&date=2017-03-01&anchor=para_8_e&doctype=Standard
-URIDate 2017-03-09

+ Details

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