Shareholders’ equity and earnings per share - Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Numerator:
Net income attributable to Sonoco	$ 44,899	$ 92,064	$ 81,159	$ 73,663	$ 77,678	$ 72,415	$ 89,412	$ 74,055	$ 291,785	$ 313,560	$ 175,345
Denominator:
Weighted average common shares outstanding (in shares)									100,742	100,539	100,237
Dilutive effect of stock-based compensation (in shares)									434	477	615
Diluted (in shares)									101,176	101,016	100,852
Net income attributable to Sonoco:
Basic (usd per share)	$ 0.45	$ 0.91	$ 0.81	$ 0.73	$ 0.78	$ 0.72	$ 0.89	$ 0.74	$ 2.90	$ 3.12	$ 1.75
Diluted (usd per share)	$ 0.44	$ 0.91	$ 0.80	$ 0.73	$ 0.77	$ 0.72	$ 0.88	$ 0.73	$ 2.88	$ 3.10	$ 1.74