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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-Publisher FASB
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No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

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

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- Definition

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

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Stock-based Compensation (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Stock-based Compensation (Details) - USD ($) $ in Millions	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Jul. 31, 2015
Share-based Payment Arrangement [Abstract]
Shares authorized (in shares)					500,000	7,150,000
Stock-based compensation expense	$ 1.0	$ 0.2	$ 2.1	$ 2.0
Share-based compensation, nonvested awards, compensation cost not yet recognized	$ 4.4		$ 4.4
Period for recognition of compensation on unvested stock option			1 year 9 months 18 days