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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of the cumulative effect on retained earnings net of related income tax effect.

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

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Summary of Significant Accounting Policies - Additional Information (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018 USD ($) Segment	Jan. 01, 2018 USD ($)
Accounting Policies [Abstract]
Number of reportable segments \| Segment	2
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Remaining performance obligation, percentage	40.00%
Accounting Standards Update 2018-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect on retained earnings	$ 1.3
Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative effect of new accounting principle in period of adoption		$ 8.7
Order or Production Backlog
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Remaining performance obligation	$ 524.3