Line of Credit Facility, Increase (Decrease) in Maximum Borrowing Capacity

No definition available.

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Namespace Prefix:	gpk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

+ References

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-Name Accounting Standards Codification
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from a debt funding received on a regular basis with maturities ranging from 5-10 years.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow to pay off borrowing used to receive debt funding on a regular basis with maturities ranging from 5-10 years.

+ References

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-Publisher FASB
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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Period Type:

- Details

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- Details

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- Details

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Debt - Credit Facilities (Details) € in Millions, ¥ in Millions	1 Months Ended					3 Months Ended	9 Months Ended			12 Months Ended
	Jan. 31, 2018 USD ($)	Jan. 31, 2018 EUR (€)	Oct. 31, 2014 EUR (€)	Jun. 30, 2014 USD ($)	Jun. 30, 2014 EUR (€)	Mar. 31, 2012 USD ($)	Sep. 30, 2013 USD ($)	Sep. 30, 2013 EUR (€)	Sep. 30, 2013 JPY (¥)	Dec. 31, 2012 USD ($)	Dec. 31, 2018 USD ($)	Jan. 08, 2018 USD ($)	Dec. 31, 2017 USD ($)
Line of Credit Facility [Line Items]
Long-term Debt												$ 660,000,000
Revolving credit facility	$ 1,450,000,000					$ 1,000,000,000					$ 1,696,200,000
Amortizing Loan Facility	800,000,000					$ 1,000,000,000,000
Incremental term loan										$ 300,000,000
Increase in revolving credit facilities		€ 200.0	€ 250.0	$ 86,000,000	€ 63.0			€ 75.0	¥ 2,500.0
Decrease in term loan	$ 125,000,000		€ 169.0
Capital Lease and Financing Obligations											$ 122,900,000		$ 30,000,000
Europe
Line of Credit Facility [Line Items]
Increase in revolving credit facilities							$ 100,000,000
JAPAN
Line of Credit Facility [Line Items]
Increase in revolving credit facilities							$ 25,000,000
Minimum
Line of Credit Facility [Line Items]
LIBOR plus variable spread	1.25%	1.25%	1.25%			1.75%	1.50%	1.50%	1.50%
Maximum
Line of Credit Facility [Line Items]
LIBOR plus variable spread	2.00%	2.00%	2.25%			2.75%	2.50%	2.50%	2.50%
Senior Notes \| Senior Notes Payable in 2021
Line of Credit Facility [Line Items]
Stated interest rate											4.75%
Long-term Debt											$ 425,000,000		425,000,000
Senior Notes \| Senior Notes Payable in 2022
Line of Credit Facility [Line Items]
Stated interest rate											4.875%
Long-term Debt											$ 250,000,000		250,000,000
Senior Notes \| Senior Notes Payable in 2024
Line of Credit Facility [Line Items]
Stated interest rate											4.125%
Long-term Debt											$ 300,000,000		$ 300,000,000