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Leases - Future Base Rental Revenue for Topic 842 (Details) $ in Thousands | Sep. 30, 2019 USD ($)
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Leases [Abstract] |
For the remainder of 2019 | $ 34,563
2020 | 139,268
2021 | 131,505
2022 | 123,894
2023 | 125,257
2024 | 133,429
Thereafter | $ 613,983

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- Definition Lessor, Operating Lease, Payments to be Received, Six Years + References No definition available. + Details
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Namespace Prefix: | alx_
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Balance Type: | debit
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- Definition Lessor, Operating Lease, Payments to be Received, after Year Six + References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount of lease payments to be received by lessor in fifth fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest statement of financial position date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981 + Details
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- Definition Amount of lease payments to be received by lessor in fourth year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981 + Details
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- Definition Amount of lease payments to be received by lessor in remainder of fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981 + Details
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- Definition Amount of lease payments to be received by lessor in third fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981 + Details
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- Definition Amount of lease payments to be received by lessor in second fiscal year following latest fiscal year for operating lease. Excludes interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 30 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919396-209981 + Details
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