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Fixed interest rate related to the interest rate derivative.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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LONG-TERM DEBT - Narrative (Detail)			1 Months Ended	12 Months Ended
LONG-TERM DEBT - Narrative (Detail)	Oct. 31, 2016 USD ($)	Jun. 22, 2016 USD ($)	Aug. 31, 2013 USD ($)	Dec. 31, 2017 USD ($) investor	Dec. 31, 2016 USD ($)	Nov. 30, 2016 USD ($)	Jun. 05, 2014 USD ($)	Jan. 12, 2012 USD ($)
Debt Instrument [Line Items]
Weighted average interest rate (as a percent)				2.92%
Faiveley
Debt Instrument [Line Items]
Liabilities assumed						$ 1,564,431,000
Interest rate swap agreements
Debt Instrument [Line Items]
Interest rate swap agreements, notional amount				$ 150,000,000			$ 150,000,000.0	$ 150,000,000.0
Interest rate on notional value (as a percent)							2.56%	1.415%
Senior Notes Due 2026
Debt Instrument [Line Items]
Stated interest rate (as a percent)				3.45%
Long-term debt				$ 747,655,000	$ 747,474,000
4.375% Senior Notes
Debt Instrument [Line Items]
Stated interest rate (as a percent)				4.375%
Long-term debt				$ 248,567,000	248,310,000
Two Thousand Sixteen Refinancing Credit Agreement
Debt Instrument [Line Items]
Deferred financing cost		$ 3,300,000
Minimum interest expense coverage ratio				3.0
Maximum debt to cash flow ratio				3.25
Two Thousand Sixteen Refinancing Credit Agreement \| Federal Funds Effective Swap Rate
Debt Instrument [Line Items]
Debt instrument basis points spread on variable rate				0.50%
Two Thousand Sixteen Refinancing Credit Agreement \| LIBOR
Debt Instrument [Line Items]
Debt instrument basis points spread on variable rate				1.00%
Two Thousand Sixteen Refinancing Credit Agreement \| Base Rate
Debt Instrument [Line Items]
Debt instrument basis points spread on variable rate				0.00%
Two Thousand Sixteen Refinancing Credit Agreement \| Base Rate \| Minimum
Debt Instrument [Line Items]
Debt instrument basis points spread on variable rate				0.00%
Two Thousand Sixteen Refinancing Credit Agreement \| Base Rate \| Maximum
Debt Instrument [Line Items]
Debt instrument basis points spread on variable rate				0.75%
Two Thousand Sixteen Refinancing Credit Agreement \| Alternative Rate
Debt Instrument [Line Items]
Debt instrument basis points spread on variable rate				1.75%
Two Thousand Sixteen Refinancing Credit Agreement \| Alternative Rate \| Minimum
Debt Instrument [Line Items]
Debt instrument basis points spread on variable rate				0.75%
Two Thousand Sixteen Refinancing Credit Agreement \| Alternative Rate \| Maximum
Debt Instrument [Line Items]
Debt instrument basis points spread on variable rate				1.75%
Two Thousand Sixteen Refinancing Credit Agreement \| Letter of Credit
Debt Instrument [Line Items]
Long-term line of credit				$ 35,400,000
Schuldschein Loan
Debt Instrument [Line Items]
Long-term debt				$ 11,998,000	98,671,000
Schuldschein Loan \| Faiveley
Debt Instrument [Line Items]
Stated interest rate (as a percent)				4.00%
Liabilities assumed				$ 137,200,000
Number of investors \| investor				20
Repayments of debt				$ 125,300,000
Long-term debt				$ 12,000,000
Senior Notes \| Senior Notes Due 2026
Debt Instrument [Line Items]
Debt instrument face amount	$ 750,000,000.0
Debt issuance face value (as a percent)	99.965%
Stated interest rate (as a percent)	3.45%			3.45%
Deferred financing cost	$ 2,700,000
Long-term debt				$ 747,655,000	747,474,000
Senior Notes \| 4.375% Senior Notes
Debt Instrument [Line Items]
Debt instrument face amount			$ 250,000,000.0
Debt issuance face value (as a percent)			99.879%
Stated interest rate (as a percent)			4.375%	4.375%
Deferred financing cost			$ 2,600,000
Long-term debt				$ 248,567,000	248,310,000
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt				853,124,000	$ 796,150,000
Line of Credit \| Two Thousand Sixteen Refinancing Credit Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit facility, amount		$ 1,200,000,000.0
Credit facility loan term, years		5 years
Line of credit facility, amount currently available				$ 679,000,000
Line of Credit \| Two Thousand Sixteen Refinancing Credit Agreement \| Term Loan
Debt Instrument [Line Items]
Revolving credit facility, amount		$ 400,000,000
Commitment fee (as a percent)		0.10%