Debt (Detail) - Borrowings (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Debt Instrument [Line Items]
Amount Outstanding	$ 665,000	[1]	$ 405,000	[1]
Term loans
Debt Instrument [Line Items]
Amount Outstanding	395,000	[2]	400,000	[2]
Revolver loans
Debt Instrument [Line Items]
Amount Outstanding	265,000	[2],[3]	0	[2],[3]
Other
Debt Instrument [Line Items]
Amount Outstanding	$ 5,000	[4]	$ 5,000	[4]

[1] The average annual effective rate on the Company's total debt outstanding as of March 31, 2015, including the effect of the swaps, was approximately 2.50%

[2] The contractual annualized interest rates as of March 31, 2015 on the term loan and the revolver ranged from 1.43% to 1.53%, which consisted of a floating eurodollar base rate ranging from 0.18% to 0.28% plus a margin of 1.25%. However, the Company has two interest rate swap contracts which convert the floating eurodollar base rates to a fixed base rate on the first $400.0 million of Company borrowings (see below).

[3] The Company had $831.8 million of available borrowing capacity on the revolver (not including the expansion feature) as of March 31, 2015.

[4] Consists of a $5.0 million State of Connecticut economic development loan with a 3.0% fixed rate of interest. The loan was originated in 2012 and has a 10 years maturity. Principal payments are deferred for the first five years and the loan may be repaid at any point by the Company without penalty. The loan has a principal forgiveness provision in which up to $2.5 million of the loan may be forgiven if the Company meets certain employment targets during the first five years of the loan.