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Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Assets Rollforward (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019 | Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2018
Goodwill [Line Items] |  |  |  |  |  |  |  |
Goodwill, acquisition date fair value | $ 518.2 |  | $ 518.2 |  | $ 402.3 |  |  |
Goodwill, Impairment Loss |  |  |  |  | 7.6 |  |  |
Goodwill | 518.2 |  | 518.2 |  | 394.7 |  |  |
Other intangible assets, acquisition date fair value | 806.0 |  | 806.0 |  | 694.4 |  |  |
Other intangible assets, accumulated amortization | 39.9 |  | 39.9 |  | 29.3 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | (10.4) |  |  |
Goodwill and intangible assets, net carrying value | 759.9 |  | 759.9 |  | 654.7 |  |  |
Payments to Acquire Intangible Assets |  | $ 82.5 |  | $ 82.5 |  |  |  |
NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Goodwill, acquisition date fair value | 504.9 |  | 504.9 |  | 381.6 |  |  |
Goodwill | 504.9 |  | 504.9 |  | 381.6 |  |  |
Other intangible assets, acquisition date fair value | 268.6 |  | 268.6 |  | 271.7 |  |  |
Other intangible assets, accumulated amortization | 38.7 |  | 38.7 |  | 27.9 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | (2.4) |  |  |
Other intangible assets, net carrying value | 223.7 |  | 223.7 |  | 241.4 |  |  |
Amortization of Intangible Assets | (6.3) | (4.1) | (11.1) | (9.1) |  |  |  |
Kudu investments |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Goodwill, acquisition date fair value | 7.6 |  | 7.6 |  | 7.6 |  |  |
Goodwill | 7.6 |  | 7.6 |  | 7.6 |  |  |
Amortization of Intangible Assets | (0.1) | 0.0 | (0.2) | 0.0 |  |  |  |
Other |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Goodwill, acquisition date fair value | 5.7 |  | 5.7 |  | 13.1 |  |  |
Goodwill, Impairment Loss |  |  |  |  | 7.6 |  |  |
Goodwill | 5.7 |  | 5.7 |  | 5.5 |  |  |
Other intangible assets, acquisition date fair value | 17.0 |  | 17.0 |  | 18.2 |  |  |
Other intangible assets, accumulated amortization | 0.8 |  | 0.8 |  | 1.2 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | (0.4) |  |  |
Other intangible assets, net carrying value | 16.2 |  | 16.2 |  | 16.6 |  |  |
Customer relationships | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 120.1 |  | 120.1 |  | 121.7 |  |  |
Other intangible assets, accumulated amortization | 26.9 |  | 26.9 |  | 19.8 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | (1.4) |  |  |
Other intangible assets, net carrying value | 89.7 |  | $ 89.7 |  | 100.5 |  |  |
Acquired finite-lived intangible assets, weighted average useful life |  |  | 9 years |  |  |  |  |
Customer relationships | Other |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 7.2 |  | $ 7.2 |  | 7.2 |  |  |
Other intangible assets, accumulated amortization | 0.6 |  | 0.6 |  | 0.4 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | 0.0 |  |  |
Other intangible assets, net carrying value | 6.6 |  | $ 6.6 |  | 6.8 |  |  |
Acquired finite-lived intangible assets, weighted average useful life |  |  | 11 years |  |  |  |  |
Trade names | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 61.2 |  | $ 61.2 |  | 61.9 |  |  |
Other intangible assets, accumulated amortization | 6.6 |  | 6.6 |  | 5.3 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | (0.4) |  |  |
Other intangible assets, net carrying value | 53.6 |  | $ 53.6 |  | 56.2 |  |  |
Acquired finite-lived intangible assets, weighted average useful life |  |  | 19 years |  |  |  |  |
Trade names | Kudu investments |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 2.2 |  | $ 2.2 |  | 2.2 |  |  |
Other intangible assets, accumulated amortization | 0.4 |  | 0.4 |  | 0.2 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | 0.0 |  |  |
Other intangible assets, net carrying value | 1.8 |  | $ 1.8 |  | 2.0 |  |  |
Acquired finite-lived intangible assets, weighted average useful life |  |  | 7 years |  |  |  |  |
Trade names | Other |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 1.0 |  | $ 1.0 |  | 1.7 |  |  |
Other intangible assets, accumulated amortization | 0.1 |  | 0.1 |  | 0.5 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | (0.2) |  |  |
Other intangible assets, net carrying value | 0.9 |  | $ 0.9 |  | 1.0 |  |  |
Acquired finite-lived intangible assets, weighted average useful life |  |  | 10 years |  |  |  |  |
Information technology | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 3.1 |  | $ 3.1 |  | 3.9 |  |  |
Other intangible assets, accumulated amortization | 1.4 |  | 1.4 |  | 1.4 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | (0.6) |  |  |
Other intangible assets, net carrying value | 0.0 |  | 0.0 |  | 1.9 |  |  |
Information technology | Other |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 0.0 |  | 0.0 |  | 0.5 |  |  |
Other intangible assets, accumulated amortization | 0.0 |  | 0.0 |  | 0.3 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | (0.2) |  |  |
Other intangible assets, net carrying value | 0.0 |  | $ 0.0 |  | 0.0 |  |  |
Acquired finite-lived intangible assets, weighted average useful life |  |  | 5 years |  |  |  |  |
Other | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 1.7 |  | $ 1.7 |  | 1.7 |  |  |
Other intangible assets, accumulated amortization | 1.0 |  | 1.0 |  | 0.7 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | 0.0 |  |  |
Other intangible assets, net carrying value | 0.7 |  | $ 0.7 |  | 1.0 |  |  |
Acquired finite-lived intangible assets, weighted average useful life |  |  | 3 years |  |  |  |  |
Other | Other |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 0.2 |  | $ 0.2 |  | 0.2 |  |  |
Other intangible assets, accumulated amortization | 0.1 |  | 0.1 |  | 0.0 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | 0.0 |  |  |
Other intangible assets, net carrying value | 0.1 |  | $ 0.1 |  | 0.2 |  |  |
Acquired finite-lived intangible assets, weighted average useful life |  |  | 5 years |  |  |  |  |
Renewal Rights |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Acquisitions of businesses |  |  | $ 0.0 |  |  |  |  |
Payments to Acquire Intangible Assets |  | 82.5 |  | 82.5 |  |  |  |
Renewal Rights | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 82.5 |  | 82.5 |  | 82.5 |  |  |
Other intangible assets, accumulated amortization | 2.8 |  | 2.8 |  | 0.7 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | 0.0 |  |  |
Other intangible assets, net carrying value | 79.7 |  | $ 79.7 |  | 81.8 |  |  |
Acquired finite-lived intangible assets, weighted average useful life |  |  | 12 years |  |  |  |  |
Other Intangible Assets |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Foreign currency translation | 0.1 | 0.2 | $ (0.4) | 0.5 |  |  |  |
Measurement Period Adjustments | 0.0 | 0.0 | 0.0 | 5.9 |  |  |  |
Intangible Assets, Net (Excluding Goodwill) | 241.7 | 239.0 | 241.7 | 239.0 | 260.0 | $ 254.4 | $ 160.5 | $ 157.6
Other intangible assets, acquisition date fair value | 287.8 |  | 287.8 |  | 292.1 |  |  |
Other intangible assets, accumulated amortization | 39.9 |  | 39.9 |  | 29.3 |  |  |
Impairment of Intangible Assets, Finite-lived | (6.2) |  | (6.2) |  | (2.8) |  |  |
Other intangible assets, net carrying value | 241.7 |  | 241.7 |  | 260.0 |  |  |
Deconsolidation of Business |  |  |  | (23.5) |  |  |  |
Amortization of Intangible Assets | (6.6) | (4.2) | (11.7) | (10.8) |  |  |  |
Goodwill, Acquired During Period |  |  | 0.0 | 0.0 |  |  |  |
Acquisitions of businesses | 0.0 | 0.0 | 0.0 | 26.8 |  |  |  |
Licensing Agreements [Member] | Other |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Other intangible assets, acquisition date fair value | 8.6 |  | 8.6 |  | 8.6 |  |  |
Other intangible assets, accumulated amortization | 0.0 |  | 0.0 |  | 0.0 |  |  |
Impairment of Intangible Assets, Finite-lived |  |  |  |  | 0.0 |  |  |
Other intangible assets, net carrying value | 8.6 |  | 8.6 |  | 8.6 |  |  |
Non-controlling interest |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Goodwill and intangible assets, net carrying value | (25.9) |  | (25.9) |  | (23.4) |  |  |
Total |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Goodwill and intangible assets, net carrying value | 734.0 |  | 734.0 |  | 631.3 |  |  |
Goodwill |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Measurement Period Adjustments | 0.0 | (0.3) | 0.2 |  |  |  |  |
Goodwill | 518.2 | 428.6 | 518.2 | 428.6 | 394.7 | 392.4 | 349.7 | 379.9
Deconsolidation of Business |  |  |  | (18.3) |  |  |  |
Goodwill, Acquired During Period | 125.1 | 80.4 | 125.1 | 93.8 |  |  |  |
Acquisitions of businesses |  |  | 0.0 | (26.8) |  |  |  |
Foreign currency translation | 0.7 | (1.2) | (1.8) | 0.0 |  |  |  |
Intangible Asset and Goodwill |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Foreign currency translation | 0.8 | (1.0) | (2.2) | 0.5 |  |  |  |
Measurement Period Adjustments | 0.0 | (0.3) | 0.2 | 5.9 |  |  |  |
Impairment of Intangible Assets, Finite-lived | (6.2) |  | (6.2) |  |  |  |  |
Goodwill and intangible assets, acquisition date fair value | 759.9 | 667.6 | 759.9 | 667.6 | 654.7 | $ 646.8 | $ 510.2 | $ 537.5
Deconsolidation of Business |  |  |  | (41.8) |  |  |  |
Amortization of Intangible Assets | (6.6) | (4.2) | (11.7) | (10.8) |  |  |  |
Goodwill, Acquired During Period |  |  | 125.1 | 93.8 |  |  |  |
Acquisitions of businesses | $ 125.1 | $ 80.4 | 0.0 | $ 0.0 |  |  |  |
Other Intangible Assets | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Foreign currency translation |  |  | (0.4) |  | $ 0.7 |  |  |
Fresh Insurance Services Group Limited |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Impairment of Intangible Assets, Finite-lived |  |  | (6.2) |  |  |  |  |
Fresh Insurance Services Group Limited | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Impairment of Intangible Assets, Finite-lived |  |  | (6.2) |  |  |  |  |
Fresh Insurance Services Group Limited | Customer relationships | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Impairment of Intangible Assets, Finite-lived |  |  | (3.5) |  |  |  |  |
Fresh Insurance Services Group Limited | Trade names | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Impairment of Intangible Assets, Finite-lived |  |  | (1.0) |  |  |  |  |
Fresh Insurance Services Group Limited | Information technology | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Impairment of Intangible Assets, Finite-lived |  |  | (1.7) |  |  |  |  |
Fresh Insurance Services Group Limited | Other | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Impairment of Intangible Assets, Finite-lived |  |  | 0.0 |  |  |  |  |
Fresh Insurance Services Group Limited | Renewal Rights | NSM Holding Co LLC |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Impairment of Intangible Assets, Finite-lived |  |  | 0.0 |  |  |  |  |
Fresh Insurance Services Group Limited | Other Intangible Assets |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |
Impairment of Intangible Assets, Finite-lived |  |  | $ (6.2) |  |  |  |  |

X
- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 + Details
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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