Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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The amount of identifiable intangible assets recognized as of the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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FacilitySource Acquisition - Summary of Preliminary Estimate of Amortizable Intangible Assets and Depreciable Computer Software Acquired (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 12, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Other intangible assets, accumulated amortization	$ 1,106,169		$ 1,000,738
Property and equipment, net	$ 705,469		$ 617,739
FacilitySource [Member]
Business Acquisition [Line Items]
Weighted Average Amortization Period, Intangibles	14 years 2 months 19 days
Amount Assigned at Acquisition Date, Total amortizable intangible assets acquired		$ 89,000
Amount Assigned at Acquisition Date, Property and Equipment		60,530
Other intangible assets, accumulated amortization	$ 346
Total amortizable intangible assets acquired, Net Carrying Value	$ 88,654
FacilitySource [Member] \| Trade names [Member]
Business Acquisition [Line Items]
Weighted Average Amortization Period, Intangibles	20 years
Amount Assigned at Acquisition Date, Total amortizable intangible assets acquired		50,400
Other intangible assets, accumulated amortization	$ 105
Total amortizable intangible assets acquired, Net Carrying Value	$ 50,295
FacilitySource [Member] \| Customer relationships [Member]
Business Acquisition [Line Items]
Weighted Average Amortization Period, Intangibles	6 years 8 months 1 day
Amount Assigned at Acquisition Date, Total amortizable intangible assets acquired		38,600
Other intangible assets, accumulated amortization	$ 241
Total amortizable intangible assets acquired, Net Carrying Value	$ 38,359
FacilitySource [Member] \| Computer software [Member]
Business Acquisition [Line Items]
Weighted Average Depreciation Period, Property and Equipment	10 years
Amount Assigned at Acquisition Date, Property and Equipment		$ 57,650
Accumulated Amortization and Depreciation, Property and Equipment	$ 240
Property and equipment, net	$ 57,410