Commitments And Contingent Liabilities (Narrative) (Details) $ in Millions	6 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Jun. 30, 2011 USD ($)
Loss Contingencies [Line Items]
Rent expense			$ 157	$ 150	$ 157
Accrual for environmental loss contingencies			128
Accrual for Environmental Loss Contingencies, Gross			141
Cass Lake Minnesota [Member]
Loss Contingencies [Line Items]
Accrual for environmental loss contingencies			47			$ 46
Kalamazoo River Superfund Site [Member]
Loss Contingencies [Line Items]
Loss contingency, damages sought, value		$ 19	37
San Jacinto River Superfund Site [Member]
Loss Contingencies [Line Items]
Loss contingency, damages sought, value			$ 115
Harris County San Jacinto River Superfund Site [Member]
Loss Contingencies [Line Items]
Loss Contingency, Number of Plaintiffs			600
Georgia-Pacific Consumer Products LP, Fort James Corporation and Georgia Pacific LLC Cost Recovery Action [Member] | Kalamazoo River Superfund Site [Member]
Loss Contingencies [Line Items]
Loss contingency, damages sought, value			$ 79
Ashley Furniture Lawsuit [Member]
Loss Contingencies [Line Items]
Loss contingency, number of defendants				10
Signature Industrial Services LLC et al. v. International Paper [Member]
Loss Contingencies [Line Items]
Disputed invoices, value			1
Loss Contingency, Damages Awarded, Value	$ 125		$ 137