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Share-based Compensation and Other Employment Benefit Plans - Narrative (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2022 USD ($) simulation shares | Dec. 31, 2021 USD ($) shares | Dec. 31, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Award requisite service period | 3 years |  |
Unrecognized compensation cost | $ 31.8 |  |
Unrecognized compensation cost, period of recognition (years) | 1 year 10 months 2 days |  |
Stock option grants (in shares) | shares | 0 | 0 | 0
Options outstanding, intrinsic value | $ 15.8 |  |
Options outstanding, weighted average remaining contractual term (years) | 1 year 9 months 3 days |  |
Options exercised, intrinsic value | $ 10.0 | $ 21.3 | $ 5.3
Stock purchase plans compensation expense | $ 1.1 | 1.1 | 1.1
Performance Share Units |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of simulations | simulation | 100,000 |  |
Non-option awards vested, total fair value | $ 2.2 | $ 2.4 | $ 7.9
Performance Share Units (PSUs) |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Vesting period | 3 years |  |
Percentage of awards subject to market condition | 50.00% | 50.00% | 50.00%
Percentage of awards subject to ROATCE | 50.00% |  |
Restricted Share Units |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Non-option awards vested, total fair value | $ 28.0 | $ 19.8 | $ 13.4
Minimum | Performance Share Units (PSUs) |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Options, vested and expected to vest, range based on return on average assets | 0.00% |  |
Maximum | Performance Share Units (PSUs) |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Options, vested and expected to vest, range based on return on average assets | 150.00% |  |
2021 Omnibus Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares of authorized but unissued common stock reserved for future grants (in shares) | shares | 5,800,000 |  |
Common stock, reserved for future issuance (in shares) | shares | 5,200,000 |  |

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- Definition Aggregate number of common shares reserved for future issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iv)(01) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for option awards outstanding, 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 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (e)(1) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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