Basis of presentation and significant accounting policies.

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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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- Definition

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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No definition available.

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- Definition

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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- Definition

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) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Basis of Presentation and Significant Accounting Policies [Line Items]
Right of use assets	$ 619.3
Lease liabilities	685.4
Restatement Adjustment [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Restatement of Prior Year Income, Tax Effects			$ 12.0
Impairment Charge on Reclassified Assets	12.6
Accounting Standards Update 2016-02 [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Retained earnings and prepaid expenses	$ 0.5
Fire Angel Safety Technology Group PLC [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Revenue from related parties		$ 7.5
Investment owned, percentage	23.40%
Equity Method Investment, Other than Temporary Impairment	$ 11.7
Equity Method Investments	2.9
Operating Lease Assets [Member]
Basis of Presentation and Significant Accounting Policies [Line Items]
Right of use assets	629.0
Lease liabilities	$ 687.0