Organization	12 Months Ended
Dec. 31, 2023
Organization
Organization	(1)Organization Territorial Bancorp Inc. is a Maryland corporation and is the holding company for Territorial Savings Bank. Territorial Savings Bank is a Hawaii state-chartered bank headquartered in Honolulu, Hawaii and is a member of the Federal Reserve System. Territorial Savings Bank has one subsidiary, Territorial Financial Services, Inc.

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480424/946-10-50-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480424/946-10-50-2

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 810
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//810/tableOfContent

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 205
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//205/tableOfContent

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