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 Corridor Percentage

+ 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.

+ Details

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- Definition

Pension benefits expected to be paid from employer assets.

+ References

No definition available.

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accumulated Benefit Obligation
-URI http://asc.fasb.org/extlink&oid=6503844

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

The amount of employer securities or securities of parties related to the employer that are included in plan assets.

+ References

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- Definition

1) For defined benefit pension plans, the benefit obligation is the projected benefit obligation, which is the actuarial present value as of a date of all benefits attributed by the pension benefit formula to employee service rendered prior to that date. 2) For other postretirement defined benefit plans, the benefit obligation is the accumulated postretirement benefit obligation, which is the actuarial present value of benefits attributed to employee service rendered to a particular date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Projected Benefit Obligation
-URI http://asc.fasb.org/extlink&oid=6522206

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accumulated Postretirement Benefit Obligation
-URI http://asc.fasb.org/extlink&oid=6503904

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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

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 35
-Paragraph 50
-URI http://asc.fasb.org/extlink&oid=64937038&loc=d3e12355-114930

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6749337

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Assets
-URI http://asc.fasb.org/extlink&oid=6520858

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of dividend income on nonoperating securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Employee Benefit Plans - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($) plan
Defined Benefit Plan Disclosure [Line Items]
Amortization period of plan assets gains and losses (in years)	5 years
Corridor percentage	10.00%
Pension benefits expected to be paid from employer assets in next fiscal year	$ 8,206
Number of plans \| plan			2
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	$ 56,975	$ 55,066	$ 53,351
Prior to 2014, U.S. Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Matching contribution to be received by pension plan participants of a specified percentage of employee's salary	20.00%
First percentage of employee's salary out of which matching contribution will be made	6.00%
Other Employees [Member]
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%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations	$ 2,306,859	2,199,356	2,352,094
Total accumulated benefit obligations	2,281,648	2,179,626
Fair value of plan assets	1,965,502	1,912,736	$ 2,021,837
Genuine Parts Company common stock included in equity securities	$ 192,841	$ 173,363
Genuine Parts Company common stock as a percentage of total plan assets	10.00%	9.00%
Dividend payments on Genuine Parts Company common stock received by plan	$ 5,308	$ 4,965
Expected rate of return on plan assets for measuring next fiscal year pension cost or income	7.82%
Pension Benefits [Member] \| S&P 500 Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	47.00%
Pension Benefits [Member] \| Russell Mid Cap Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	5.00%
Pension Benefits [Member] \| Russell 2000 Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	7.00%
Pension Benefits [Member] \| MSCI EAFE Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	5.00%
Pension Benefits [Member] \| DJ Global Moderate Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	5.00%
Pension Benefits [Member] \| MSCI Emerging Market Net [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	3.00%
Pension Benefits [Member] \| BarCap U.S. Govt/Credit [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark	28.00%
United States Pension Plan of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations	$ 2,105,665	2,012,935
Fair value of plan assets	$ 1,760,713	$ 1,731,368