XML 75 R55.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Commitments, Contingencies and Legal Proceedings (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract] |
Summary of Minimum Annual Payment Due on Noncancelable Operating Lease | The following table summarizes the minimum annual payments due on noncancelable operating leases and other similar contractual obligations having initial or remaining terms in excess of one year:
In thousands |  | Leases |  |  |  | Other |
2019 |  | $ | 5,020 |  |  |  | $ | 84,451 |
2020 |  |  | 3,861 |  |  |  |  | 22,249 |
2021 |  |  | 2,515 |  |  |  |  | 2,483 |
2022 |  |  | 1,426 |  |  |  |  | 306 |
2023 |  |  | 584 |  |  |  |  | 49 |
Thereafter |  |  | 383 |  |  |  |  | 2 |
Schedule of Reserves | Reserves for the Site. Our reserve for past and future government oversight costs and long-term monitoring and maintenance is set forth below:
|  | Year ended December 31 |
In thousands |  |  | 2018 |  |  |  |  | 2017 |
Balance at January 1, |  | $ | 43,144 |  |  |  | $ | 52,788 |
Payments |  |  | (3,054 | ) |  |  |  | (9,644 | )
Assumption of WTM I escrow |  |  | 4,746 |  |  |  |  | - |
Accretion |  |  | 165 |  |  |  |  | - |
Balance at December 31, |  | $ | 45,001 |  |  |  | $ | 43,144 |

X
- Definition Summary of minimum annual payment due on noncancelable operating lease. + References No definition available. + Details
Name: | glt_SummaryOfMinimumAnnualPaymentDueOnNoncancelableOperatingLeaseTableTextBlock
Namespace Prefix: | glt_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_CommitmentsAndContingenciesDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of environmental loss contingencies by individual site. Does not include loss contingencies that are not environmental in nature. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13296-110859 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 5.Y.Q2) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13283-110859 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13207-110859 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 10 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13237-110859 + Details
Name: | us-gaap_ScheduleOfEnvironmentalLossContingenciesBySiteTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration