Employee Retirement Plans (Narrative) (Details)	Jun. 30, 2012
Employee Retirement Plans [Abstract]
Percentage of cap on 2005 contributions toward future retiree medical coverage	120.00%
Percentage of cost to be paid by employees for retiree medical upon retirement	100.00%

Percentage of cost to be paid by employees for retiree medical upon retirement.

No definition available.

Name:	glw_PercentageOfCostToBePaidByEmployeesForRetireeMedicalUponRetirement
Namespace Prefix:	glw_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant