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Municipal Bond Guarantee - Schedule of Municipal Guarantee Insurance Contracts, Premium Received Over Contract Period (Details) - BAM - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
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Guarantor Obligations [Line Items] |  |
January 1, 2022 - March 31, 2022 | $ 6.4 |
April 1, 2022 - June 30, 2022 | 6.4 |
July 1, 2022 - September 30, 2022 | 6.3 |
October 1, 2022 - December 31, 2022 | 6.1 |
Total 2021 | 25.2 |
2023 | 23.9 |
2024 | 22.2 |
2025 | 20.6 |
2026 | 19.1 |
2027 and thereafter | 155.3 |
Total gross unearned insurance premiums | $ 266.3 | $ 237.5

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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in next fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in fourth fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in second fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in third fiscal quarter following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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- Definition Amount of premium revenue under financial guarantee insurance contract to be recognized in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 605 -Section 50 -Paragraph 4 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=6933581&loc=SL5749298-161291 + Details
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