XML 32 R46.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Gains on Dispositions of Plant, Equipment and Timberlands, Net - Summary for Sale of Timberlands and Other Assets (Detail) (USD $) In Thousands, unless otherwise specified | 9 Months Ended
--- | ---
Sep. 30, 2013 | Sep. 30, 2012
Property, Plant and Equipment [Line Items] |  |
Proceeds | $ 379 | $ 8,875
Gain | 374 | 8,471
Timberlands [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Acres | 172 | 4,324
Proceeds | 287 | 8,105
Gain | 282 | 7,867
Other [Member] |  |
Property, Plant and Equipment [Line Items] |  |
Acres |  |
Proceeds | 92 | 770
Gain | $ 92 | $ 604

X
- Definition Area of timberland. + References No definition available. + Details
Name: | glt_AreaOfTimberland
Namespace Prefix: | glt_
Data Type: | num:areaItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of gain (loss) on sale or disposal of property used for growing and harvesting trees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6391110&loc=d3e2941-110230 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 + Details
Name: | us-gaap_GainLossOnSaleOfTimberProperty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revenue from sale of timber, mill lumber, wood, and other wood products. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(a)) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
Name: | us-gaap_TimberRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration