Restructuring and asset impairment - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2017 USD ($)	Oct. 01, 2017 USD ($)	Dec. 31, 2018 USD ($) facility position	Dec. 31, 2017 USD ($) building facility	Dec. 31, 2016 USD ($)
Restructuring Cost and Reserve [Line Items]
Future additional charges expected in connection with previous restructuring			$ 1,800
Number of facilities closed (facility) | facility				5
Gain (loss ) on sale of land and buildings			(8,635)	$ (2,039)	$ (14,173)
Gain (loss) on disposition of business			$ 0	0	$ 108,699
Foreign exchange remeasurement losses on net monetary assets				$ 425
Paper and Industrial Converted Products
Restructuring Cost and Reserve [Line Items]
Goodwill, impairment loss		$ 2,617
Number 9 Boiler
Restructuring Cost and Reserve [Line Items]
Write off / impairment of assets	$ 17,822
U.S.
Restructuring Cost and Reserve [Line Items]
Number of facilities closed (facility) | facility				3
Belgium
Restructuring Cost and Reserve [Line Items]
Number of facilities closed (facility) | facility				1
China
Restructuring Cost and Reserve [Line Items]
Number of facilities closed (facility) | facility				1
Venezuela
Restructuring Cost and Reserve [Line Items]
Other asset impairments				$ 338
2018 Actions
Restructuring Cost and Reserve [Line Items]
Number of facilities closed (facility) | facility			5
Elimination of positions due to realign in cost structure (position) | position			120
Asset impairment/disposal of assets			$ 32,293
Termination fee			9,600
2018 Actions | Asset Impairment, Disposal of Assets, Land and Building
Restructuring Cost and Reserve [Line Items]
Proceeds from sale of building			2,019
Write off / impairment of assets			1,747
Disposal group, gain on disposition			272
2018 Actions | Hollister, California | Asset Impairment, Disposal of Assets, Packaging Plant
Restructuring Cost and Reserve [Line Items]
Net fixed assets			1,924
Inventory			$ 117
2018 Actions | Norway
Restructuring Cost and Reserve [Line Items]
Number of facilities closed (facility) | facility			1
2018 Actions | Russia
Restructuring Cost and Reserve [Line Items]
Number of facilities closed (facility) | facility			1
2018 Actions | Indonesia
Restructuring Cost and Reserve [Line Items]
Number of facilities closed (facility) | facility			1
2018 Actions | Atlanta, GA
Restructuring Cost and Reserve [Line Items]
Asset impairment/disposal of assets			$ 4,516
Proceeds from sale of building			22,163
Net fixed assets			24,869
Inventory			$ 1,810
2018 Actions | Alabama
Restructuring Cost and Reserve [Line Items]
Number of facilities closed (facility) | facility			1
2018 Actions | Canada
Restructuring Cost and Reserve [Line Items]
Number of facilities closed (facility) | facility			1
2017 Actions
Restructuring Cost and Reserve [Line Items]
Asset impairment/disposal of assets			$ 7,870	15,329
2017 Actions | Asset Impairment, Disposal of Assets, Packaging Plant
Restructuring Cost and Reserve [Line Items]
Other asset impairment charges				1,238
2017 Actions | Closure of Packaging Plant and Sale of Vacated Buildings
Restructuring Cost and Reserve [Line Items]
Proceeds from sale of building				636
Write off / impairment of assets				525
2017 Actions | Asset Impairment, Disposal of Assets, Vacated Buildings
Restructuring Cost and Reserve [Line Items]
Gain (loss ) on sale of land and buildings				$ 111
Number of buildings vacated (building) | building				2
2017 Actions | Sale of Land and Buildings of Closed Tube Facilities and Recovered Paper Facilities
Restructuring Cost and Reserve [Line Items]
Proceeds from sale of building			2,006
Write off / impairment of assets			577
Gain (loss) on disposition of business			1,429
2017 Actions | Other Restructuring Actions Initiated in 2017
Restructuring Cost and Reserve [Line Items]
Write off / impairment of assets			620
2017 Actions | Closure of Packaging Services Center in Mexico
Restructuring Cost and Reserve [Line Items]
Termination fee			1,931
2016 and Earlier Actions
Restructuring Cost and Reserve [Line Items]
Asset impairment/disposal of assets			$ (92)	$ 5,614
Proceeds from sale of building				2,741
Write off / impairment of assets				719
Future pretax charges	$ 100			100
2016 and Earlier Actions | Asset Impairment, Disposal of Assets, Land and Building
Restructuring Cost and Reserve [Line Items]
Asset impairment/disposal of assets				$ 2,022