Defined Benefit Plan Assumptions Used Calculating Net Periodic Benefit Cost Expected Long Term Return On Assets.

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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

First percentage of employees salary out of which matching contribution will be made.

+ References

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First percentage of other employees salary out of which matching contribution will be made.

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- Definition

Highest credit service of a specified period for benefits on employees contributions.

+ References

No definition available.

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Last credit service period for benefits on employees compensation.

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- Definition

Matching contribution to be received by other employees of specified percentage of other employees salary.

+ References

No definition available.

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- Definition

Matching contribution to be received by pension plan participants of a specified percentage of employee's salary.

+ References

No definition available.

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- Definition

Non cash curtailment adjustment.

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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

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 Statement of Financial Accounting Standard (FAS)

-Number 132R

-Paragraph 5

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Benefit Obligation

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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

-Glossary Projected Benefit Obligation

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Accumulated Postretirement Benefit Obligation

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- Definition

Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.

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- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

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-Glossary Health Care Cost Trend Rate

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- Definition

The ultimate trend rate for health care costs.

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- Definition

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

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 132R

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Income derived from investments in equity securities representing a distribution of earnings to shareholders by the investee companies.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

-Paragraph 7

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-Name Statement of Financial Accounting Standard (FAS)

-Number 115

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Employee Benefit Plans (Details Textual) (USD $)	1 Months Ended	12 Months Ended
Employee Benefit Plans (Details Textual) (USD $)	Apr. 30, 2009	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets for the Company's US pension plans		$ 1,470,030,000	$ 1,439,711,000
Employee Benefit Plans (Textual) [Abstract]
Highest credit service of a specified period for benefits on employees contributions		5 years
Last credit service period for benefits on employees compensation		10 years
Non Cash Curtailment Adjustment	4,298,000
Assumed annual rate of increase in per capita cost of covered health care benefits		8.00%	7.75%
Assumed rate to which per capita cost of covered health care benefits will ratably decrease to		4.80%	4.75%
Genuine Parts Company common stock included in equity securities		123,436,000	103,549,000
Genuine Parts Company common stock as a percentage of total plan assets		8.40%	7.20%
Dividend payments on Genuine Parts Company common stock received by plan		3,630,000	3,308,000
Pension benefits expected to be paid from employer assets in 2012		4,985,000
Total defined contribution plans expense		38,773,000	33,476,000	31,783,000
Matching contribution to be received by pension plan participants of a specified percentage of employee's salary		20.00%
First percentage of employees salary out of which matching contribution will be made		6.00%
Matching contribution to be received by other employees of a specified percentage of other employees salary		100.00%
First percentage of other employees salary out of which matching contribution will be made		5.00%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets for measuring 2012 pension cost or income		7.84%
Total accumulated benefit obligations for company's defined benefit pension plans		1,756,546,000	1,526,951,000
Benefit obligations for company's US plans		1,958,399,000	1,689,011,000	1,502,084,000
Fair value of plan assets for the Company's US pension plans		1,470,030,000	1,439,711,000	1,216,415,000
United States Pension Plans of US Entity, Defined Benefit [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefit obligations for company's US plans		1,775,994,000	1,542,469,000
Fair value of plan assets for the Company's US pension plans		$ 1,320,036,000	$ 1,294,348,000
BarCap US Govt Credit [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark		30.00%
MSCI EAFE Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark		5.00%
Russell Two Thousand Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark		10.00%
Russell Mid Cap Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark		5.00%
S&P 500 Index [Member]
Defined Benefit Plan Disclosure [Line Items]
Passive portfolio benchmark		50.00%