Reportable Segments (Narrative) (Details)	9 Months Ended
Sep. 30, 2018 item
Reportable Segments [Abstract]
Number of Material Formulations	150
Segment tax rate	21.00%

The number of material formulations for glass, glass ceramics and fluoride crystals provided by the Specialty Materials Segment.

No definition available.

Name:	glw_NumberOfMaterialFormulations
Namespace Prefix:	glw_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration