Income tax and tax loss carryforwards, Tax loss carryforwards (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 MXN ($)
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 3,309,791
2008 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 109,685
Year of expiration	2018
2009 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 389,543
Year of expiration	2019
2010 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 537,231
Year of expiration	2020
2011 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 352,239
Year of expiration	2021
2012 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 538,601
Year of expiration	2022
2013 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 389,355
Year of expiration	2023
2014 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 244,640
Year of expiration	2024
2015 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 151,575
Year of expiration	2025
2016 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 488,472
Year of expiration	2026
2017 - Year Loss Incurred [Member]
Tax loss carryforwards [Abstract]
Tax loss carryforward amount	$ 108,450
Year of expiration	2027