Payout Percentage If Performance Metric Achieved

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- Definition

Performance Metric, Potential Range

+ References

No definition available.

+ Details

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- Definition

The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Stock-based Compensation (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, net of taxes	$ 3.2	$ 2.4	$ 8.4	$ 6.6
Market-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Shares			31,688	56,571
Average period based on relative TSR			3 years
Market-based awards \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric achieved	100.00%		100.00%
Performance And Market-Based Restricted Stock Units \| Minimum [Member] \| Senior management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric, potential range			0.00%
Performance And Market-Based Restricted Stock Units \| Maximum [Member] \| Senior management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric, potential range			150.00%
Market Based Awards That Achieved Payout In Excess Of 1[Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Shares			3,115	5,881
Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Shares			0	0
Performance metric achieved	100.00%		100.00%
Performance-based restricted stock units \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric, potential range			0.00%
Performance-based restricted stock units \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric, potential range			200.00%
Chaucer [Member] \| Discontinued Operations [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense, net of taxes	$ 0.4	$ 0.3	$ 1.2	$ 0.9
2014 Stock Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	4,065,238		4,065,238
ESPP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	2,378,832		2,378,832
SIP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant	678,183		678,183