Borrowings - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	May. 31, 2015	Dec. 31, 2015	May. 12, 2015	May. 03, 2012
2015 Credit Agreement [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 440,000,000
Line of credit facility, expiration date		May 12, 2020
Varying installments due		$ 0
Credit agreement interest rate description		Borrowings under the 2015 Credit Agreement will bear interest at either LIBOR or the base rate plus, in each case, an applicable margin based on the Company’s leverage ratio. The applicable interest rate will be determined quarterly based on the Company’s leverage ratio at such time. The base rate is a rate per annum equal to the greatest of (i) the rate of interest established by KeyBank, from time to time, as its “prime rate”; (ii) the Federal Funds effective rate in effect from time to time, plus 1/2 of 1% per annum; and (iii) the then-applicable LIBOR rate for one month interest periods, plus 1.00%. Swingline loans will bear interest only at the base rate plus the base rate margin.
Fixed component added to federal fund effective rate to compute base rate		0.50%
Fixed component added to LIBOR to compute base rate		1.00%
Commitment fee		0.125%
Credit agreement customary fees description		The Company is required to pay certain customary fees, including a commitment fee of 0.125%, which is due quarterly in arrears and calculated on the average unused amount of the 2015 Credit Agreement.
Underwriting fee for credit agreement	$ 900,000
2015 Credit Agreement [Member] | Non-Voting Capital Stock Direct Foreign Subsidiaries [Member]
Line of Credit Facility [Line Items]
Percentage of capital stock pledged under credit agreement		100.00%
2015 Credit Agreement [Member] | Voting Capital Stock Direct Foreign Subsidiaries [Member]
Line of Credit Facility [Line Items]
Percentage of capital stock pledged under credit agreement		65.00%
2012 Credit Agreement [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity				$ 245,000,000
Underwriting fee for credit agreement		$ 400,000
Deferred loan fees expensed	$ 100,000
2015 Credit Agreement Alternate-Currency Sub-Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity			200,000,000
2015 Credit Agreement Swingline Sub-Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity			10,000,000
2015 Credit Agreement Letter of Credit Sub-Facility [Member]
Line of Credit Facility [Line Items]
Maximum borrowing capacity			$ 35,000,000