XML 34 R79.htm IDEA: XBRL DOCUMENT v2.4.0.8

Income Taxes - Schedule of Unrecognized Tax Benefit (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Reserve for an uncertain tax position	$ 1.3

X

- Definition

Reserve for uncertain tax position recorded in purchase accounting to acquisition.

+ References

No definition available.

+ Details

Name:	glt_ReserveForUncertainTaxPositionRecordedInPurchaseAccountingToAcquisition
Namespace Prefix:	glt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Details

Name:	us-gaap_IncomeTaxDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration