Project debt, movement in project debt, split between cash and non-cash items (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Project debt [Abstract]
Beginning balance	$ 5,475,208
Cash flow	(579,598)
Non-cash changes	195,504
Ending balance	$ 5,091,114

The change due to current and non-current portions of project debt issued at the project level under project finance during the period - non-cash movement.

No definition available.

Name:	aby_MovementInLongTermAndShortTermProjectDebtNonCashCharges
Namespace Prefix:	aby_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration