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Employee benefit plans - Additional Information (Details)	12 Months Ended			144 Months Ended
	Dec. 31, 2023 USD ($) participant year	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)	Sep. 08, 2023 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plans, accumulated benefit obligation	$ 404,648,000	$ 347,608,000
Projected benefit obligation (PBO) with accumulated benefit obligations in excess of plan assets	229,397,000	176,702,000
Accumulated benefit obligation (ABO) with accumulated benefit obligations in excess of plan assets	224,045,000	171,705,000
Fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets	84,929,000	48,277,000
Total postretirement benefit plan assets	308,800,000	$ 265,875,000
Loss from plan amendment affecting accumulated postretirement benefit obligation and prior service cost	11,637,000
Projected contributions to retirement plan	$ 19,000,000
Percentage of retiree health liability	98.00%
RTS Packaging
Defined Benefit Plan Disclosure [Line Items]
Voting interest acquired					65.00%
Interest held in acquiree before subsequent acquisition (percent)					35.00%
Accumulated other comprehensive loss including define pension plan, before tax					$ 4,756,000
Accumulated other comprehensive loss including define pension plan, after tax					3,543,000
U.K.
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	100.00%	100.00%
Canada
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	100.00%	100.00%
United States
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	100.00%	100.00%
Sonoco Savings Plan
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan contribution percentage, minimum	1.00%
Defined contribution plan contribution percentage, maximum	100.00%
Defined contribution plan, employer matching contribution (percent)			100.00%
Employer matching contribution, percent of employees' gross pay (percent)			6.00%
Percentage of participants modified matching contribution to be matched towards safe Harbor under companies savings plan				50.00%
Modify matching employee contribution to profit sharing under companies savings plan				4.00%
Companies expense related to the plan	$ 41,000,000	$ 38,900,000	$ 13,900,000
Sonoco Investment and Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Companies expense related to the plan	$ 0	0	22,914,000
Contribution rate of annual eligible earnings under companies investment and retirement plan	4.00%
Contribution rate of annual eligible earnings in excess of social security wage base under companies investment and retirement plan	4.00%
Vesting period	3 years
Age limit of participants (year) \| year	55
Cash contributions to the SIRP	$ 0	21,948,000	22,665,000
RTS Packaging Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	93.00%
Retirement Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, benefit obligation	$ 413,456,000	352,843,000	514,633,000	$ 514,633,000
Total postretirement benefit plan assets	295,587,000	253,125,000	417,105,000	417,105,000
Accumulated other comprehensive loss including define pension plan, before tax	(114,957,000)	(109,558,000)
Loss from plan amendment affecting accumulated postretirement benefit obligation and prior service cost	5,557,000	6,053,000
Retirement Plans \| Canada
Defined Benefit Plan Disclosure [Line Items]
Non-cash settlement charges	$ 1,010,000	$ 479,000	11,984,000
Retirement Plans \| Equity securities \| U.K.
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	20.00%	22.60%
Current target allocation for investment portfolio	20.00%
Retirement Plans \| Equity securities \| Canada
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	29.40%	34.00%
Current target allocation for investment portfolio	29.00%
Retirement Plans \| Equity securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	22.20%	23.40%
Retirement Plans \| Debt securities \| U.K.
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	79.10%	76.30%
Current target allocation for investment portfolio	80.00%
Retirement Plans \| Debt securities \| Canada
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	70.60%	66.00%
Current target allocation for investment portfolio	71.00%
Retirement Plans \| Debt securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	76.60%	72.90%
Retirement Plans \| Cash and short-term investments \| U.K.
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	0.90%	1.10%
Retirement Plans \| Cash and short-term investments \| Canada
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	0.00%	0.00%
Retirement Plans \| Cash and short-term investments \| United States
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	1.20%	3.70%
Retirement Plans \| Inactive Plan Investment Portfolio
Defined Benefit Plan Disclosure [Line Items]
Projected contributions to retirement plan	$ 124,432,000
Expected settlement charge	$ 538,722,000
Number of participants \| participant	11,000
Retirement Plans \| Active Plan Investment Portfolio
Defined Benefit Plan Disclosure [Line Items]
Number of participants \| participant	700
Retirement Plans \| Active Plan Investment Portfolio \| Equity securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Current target allocation for investment portfolio	20.00%
Retirement Plans \| Active Plan Investment Portfolio \| Debt securities \| United States
Defined Benefit Plan Disclosure [Line Items]
Current target allocation for investment portfolio	80.00%
Retirement Plans \| RTS Packaging Pension Plan \| United States
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, benefit obligation					43,934,000
Total postretirement benefit plan assets					32,322,000
Defined benefit plan, long-term unfunded pension obligations					11,529,000
Defined benefit plan, short-term unfunded pension obligations					$ 83,000
Retirement Plans \| RTS Packaging Pension Plan \| Equity securities
Defined Benefit Plan Disclosure [Line Items]
Current target allocation for investment portfolio	20.00%
Retirement Plans \| RTS Packaging Pension Plan \| Debt securities
Defined Benefit Plan Disclosure [Line Items]
Current target allocation for investment portfolio	80.00%
Retiree Health and Life Insurance Plans
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, benefit obligation	$ 22,571,000	$ 11,244,000	13,745,000	13,745,000
Total postretirement benefit plan assets	13,213,000	12,750,000	$ 13,942,000	$ 13,942,000
Accumulated other comprehensive loss including define pension plan, before tax	6,120,000	6,437,000
Loss from plan amendment affecting accumulated postretirement benefit obligation and prior service cost	$ 11,637,000	$ 0
Total postretirement benefit plan assets (percent)	100.00%	100.00%
Retiree Health and Life Insurance Plans \| Equity securities
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	0.00%	0.00%
Retiree Health and Life Insurance Plans \| Debt securities
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	100.00%	100.00%
Retiree Health and Life Insurance Plans \| Cash and short-term investments
Defined Benefit Plan Disclosure [Line Items]
Total postretirement benefit plan assets (percent)	0.00%	0.00%