Asset Impairment Charges and Facility Closing and Reorganization Costs - Approved Plans and Related Charges (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Other	$ 0us-gaap_OtherRestructuringCosts	$ 5,000us-gaap_OtherRestructuringCosts	$ (968,000)us-gaap_OtherRestructuringCosts
Total	4,460,000us-gaap_RestructuringCharges	27,008,000us-gaap_RestructuringCharges	55,787,000us-gaap_RestructuringCharges
Closure of facilities
Restructuring Cost and Reserve [Line Items]
Closure of facilities	4,460,000	20,845,000	18,536,000
Charges incurred to date	44,000,000
Expected costs	6,900,000
Functional Realignment
Restructuring Cost and Reserve [Line Items]
Functional Realignment	0	892,000	32,219,000
Charges incurred to date	33,100,000
Field and Functional Reorganization
Restructuring Cost and Reserve [Line Items]
Severance Costs	0	5,266,000	6,000,000
Charges incurred to date	$ 11,300,000

Severance Costs Asset Writedowns And Other Related Costs

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses associated with a discontinued operation or an asset retirement obligation.

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Amount of costs incurred to date for the specified type of restructuring cost.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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