Amortization period of defined benefit plan assets gain loss.

No definition available.

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- Definition

Defined benefit plan assumptions used calculating net periodic benefit cost expected long term return on assets for next fiscal year.

+ References

No definition available.

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- Definition

Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss), Demographic Experience

+ References

No definition available.

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- Definition

Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss), Discount Rate Change

+ References

No definition available.

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- Definition

Defined benefit plan percentage of employer and related party securities included in plan assets.

+ References

No definition available.

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- Definition

Defined Contribution Plan, Number of Plans

+ References

No definition available.

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- Definition

Passive portfolio benchmark.

+ References

No definition available.

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- Definition

Pension benefits expected to be paid from employer assets.

+ References

No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ References

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- Definition

Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

+ References

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

+ References

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

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- Definition

Amount of increase in benefit obligation for benefits provided to employees payable from defined benefit plan or payable upon retirement.

+ References

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

+ References

No definition available.

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Percentage employer matches of the employee's percentage contribution matched.

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- Definition

Amount of dividend income on nonoperating securities.

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Employee Benefit Plans - Additional Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) plan	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Amortization period of plan assets gains and losses (in years)	5 years
Benefit obligations	$ 2,532,973	$ 2,678,966	$ 2,496,600
Total accumulated benefit obligations	2,500,595	2,649,418
Actuarial (gain) loss	(87,966)	218,534
Actual return on plan assets	330,402	347,560
Special termination costs			42,757
Fair value of plan assets	$ 2,756,803	$ 2,545,359	2,311,227
Genuine Parts Company common stock as a percentage of total plan assets	8.00%	8.00%
Dividend payments on Genuine Parts Company common stock received by plan	$ 4,895	$ 6,378
Expected rate of return on plan assets for measuring next fiscal year pension cost or income	6.34%
Pension benefits expected to be paid from employer assets in next fiscal year	$ 12,548
US Large-Cap Stocks
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	38.00%
US Mid-Cap Stocks
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	9.00%
International Stocks
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	10.00%
Emerging Market Stock
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	3.00%
BarCap U.S. Govt/Credit
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	40.00%
United States
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations	$ 2,245,669	2,373,884
Fair value of plan assets	$ 2,457,907	2,258,246
Number of plans \| plan	1
Matching contribution to be received by pension plan participants of a specified percentage of employee's salary	100.00%
First percentage of employee's salary out of which matching contribution will be made	5.00%
Total defined contribution plans expense	$ 59,545	54,885	$ 64,990
United States \| U.S. Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Actuarial (gain) loss	73,200
Actual return on plan assets	173,300
Loss from discount rate change	69,000
United States \| U.S. Supplemental Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Actuarial (gain) loss	5,500
Loss from discount rate change	(9,600)
Loss for participant demographic experience	$ 14,000
Canada
Defined Benefit Plan Disclosure [Line Items]
Matching contribution to be received by pension plan participants of a specified percentage of employee's salary	100.00%
First percentage of employee's salary out of which matching contribution will be made	5.00%
Total defined contribution plans expense	$ 5,196	$ 4,486