v3.21.2

Restructuring and Integration - Summary of Restructuring Costs (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Sep. 30, 2021 | Jun. 30, 2021
Restructuring Cost And Reserve [Line Items] |  |
Restructuring Costs | $ 3 | $ 9
Inception to Date | 103 |
Estimated Remaining Costs | 32 |
Estimated Total Cost | 135 |
Employer Solutions |  |
Restructuring Cost And Reserve [Line Items] |  |
Restructuring Costs | 3 | 8
Inception to Date | 90 |
Estimated Remaining Costs | 25 |
Estimated Total Cost | 115 |
Employer Solutions | Severance and Related Benefits |  |
Restructuring Cost And Reserve [Line Items] |  |
Restructuring Costs | 1 | 6
Inception to Date | 46 |
Estimated Remaining Costs | 21 |
Estimated Total Cost | 67 |
Employer Solutions | Other Restructuring Costs |  |
Restructuring Cost And Reserve [Line Items] |  |
Restructuring Costs | 2 | 2
Inception to Date | 44 |
Estimated Remaining Costs | 4 |
Estimated Total Cost | 48 |
Professional Services |  |
Restructuring Cost And Reserve [Line Items] |  |
Restructuring Costs |  | 1
Inception to Date | 13 |
Estimated Remaining Costs | 7 |
Estimated Total Cost | 20 |
Professional Services | Severance and Related Benefits |  |
Restructuring Cost And Reserve [Line Items] |  |
Restructuring Costs |  | $ 1
Inception to Date | 8 |
Estimated Remaining Costs | 5 |
Estimated Total Cost | 13 |
Professional Services | Other Restructuring Costs |  |
Restructuring Cost And Reserve [Line Items] |  |
Inception to Date | 5 |
Estimated Remaining Costs | 2 |
Estimated Total Cost | $ 7 |

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- Definition Amount of costs incurred to date for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 + Details
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- Definition Amount expected to be recognized in earnings for the specified restructuring cost. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)(1)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(d)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 + Details
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