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The minimum quantity of shares an employee can purchase under the plan per period.

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No definition available.

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Number of years over which shares to be purchased under the share-based compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of promissory notes under the share-based compensation arrangement.

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Issued, Amount

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No definition available.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

Number of shares issued under share-based payment arrangement.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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- Definition

Amount of cost expensed and capitalized for award under share-based payment arrangement.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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Employee benefit plans and compensation plans - Share-Based and Other Long-Term Incentive Compensation Plans (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	Aug. 22, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Aug. 06, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for issuance under the plan (in shares)		8,416,533
Payments for share-based awards		$ 3.3	$ 0.0	$ 0.0
Total share-based compensation expense - pre-tax		$ 4.7	$ 2.5	0.0
Non-employee independent directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Shares granted (in shares)		37,039	24,475
Total share-based compensation expense - pre-tax		$ 0.3
2018 Omnibus plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to be issued (in shares)					14,114,904
Vesting period		3 years
2016 Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		2 years
Shares granted (in shares)		0
Total share-based compensation expense - pre-tax		$ (3.4)	$ 1.0	0.0
PSUs \| 2018 Omnibus plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value (in dollars per share)		$ 12.75
Shares granted (in shares)		756,183
Total share-based compensation expense - pre-tax		$ 0.7	1.5	0.0
PSUs \| Long Term Incentive Plan 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
PSUs \| 2019 Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Grant date fair value (in dollars per share)		$ 12.75
Shares granted (in shares)		408,370
Total share-based compensation expense - pre-tax		$ 0.8	0.0	0.0
PSUs \| 2019 Long Term Incentive Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		0.00%
PSUs \| 2019 Long Term Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		200.00%
PSUs \| 2016 Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		1,428,185
Total share-based compensation expense - pre-tax		$ 5.8	0.0	0.0
RSUs \| 2019 Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant date fair value (in dollars per share)		$ 12.75
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected annual dividend yield		1.75%
Expected volatility		20.00%
Risk-free interest rate		2.51%
Expected term		4 years
Total share-based compensation expense - pre-tax		$ 0.8	$ 0.0	$ 0.0
Stock Options \| 2019 Long Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Shares issued (in shares)		1,374,945
Expiration period		5 years
Fair value of stock options		$ 2.8
Exercise price (in dollars per share)		$ 12.75
IPO Incentive Awards \| 2018 Omnibus plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of years over which shares to be purchased		3 years
IPO Incentive Awards \| 2018 Omnibus plan \| 2019 ROE
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		25.00%
IPO Incentive Awards \| 2018 Omnibus plan \| 2020 ROE
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		25.00%
IPO Incentive Awards \| 2018 Omnibus plan \| 2021 ROE
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		25.00%
IPO Incentive Awards \| 2018 Omnibus plan \| 2019-2021 Average ROE
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage		25.00%
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)		0	149,236
Maximum number of shares to be purchased (in shares)	1,000
Minimum number of shares to be purchased (in shares)	100
Net promissory notes		$ 0.4	$ 0.9
9.0% ROE \| IPO Incentive Awards \| 2018 Omnibus plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout as percentage of awarded shares		100.00%
13.5% ROE \| IPO Incentive Awards \| 2018 Omnibus plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout as percentage of awarded shares		150.00%
For the first 100 shares \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of common shares as a percentage on its market value	85.00%
For the next 900 shares \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase price of common shares as a percentage on its market value	100.00%