Basis of presentation and significant accounting policies.

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Disposal groups held for sale

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Disposal group subject to inaccurate impairment assessment

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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For the asset that is reclassified back to held and used from held-for-sale, the amount of impairment charge that is recognized on the reclassification date.

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Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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The cash inflow associated with the proceeds from sale and collection of receivables during the period.

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The tax effect of the restatement to correct an error in net income of prior periods for the year in which any adjustments are first made. In statements containing more than one period, disclose the effects for each period.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) $ in Millions		3 Months Ended			6 Months Ended		12 Months Ended
	Jan. 01, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Basis of Presentation and Significant Accounting Policies [Line Items]
Right of use assets		$ 646.0			$ 646.0		$ 0.0
Lease liabilities		701.0			701.0
Proceeds from Sale and Collection of Receivables		$ 201.0
Disposal group subject to inaccurate impairment assessment			1
Disposal groups held for sale			5
Restatement Adjustment
Basis of Presentation and Significant Accounting Policies [Line Items]
Impairment Charge on Reclassified Assets					$ 12.6
Restatement of Prior Year Income, Tax Effects							$ 12.0
Accounting Standards Update 2016-02
Basis of Presentation and Significant Accounting Policies [Line Items]
Retained earnings and prepaid expenses	$ 0.5
Fire Angel Safety Technology Group PLC
Basis of Presentation and Significant Accounting Policies [Line Items]
Investment owned, percentage		23.40%			23.40%
Equity Method Investment, Other than Temporary Impairment					$ 11.7
Equity Method Investments		$ 4.6			$ 4.6
Revenue from related parties				$ 0.0		$ 7.5
Operating Lease Assets
Basis of Presentation and Significant Accounting Policies [Line Items]
Right of use assets	629.0
Lease liabilities	$ 687.0