Financial Derivatives and Hedging Activities - Outstanding Derivatives Used to Hedge Foreign Exchange Risks (Detail)	Mar. 31, 2015 Cash Flow Hedges [Member] Euro / British Pound [Member] Designated as Hedging [Member] Sell/Buy - Sell Notional [Member] EUR (€)	Dec. 31, 2014 Cash Flow Hedges [Member] Euro / British Pound [Member] Designated as Hedging [Member] Sell/Buy - Sell Notional [Member] EUR (€)	Mar. 31, 2015 Cash Flow Hedges [Member] Euro / Philippine Peso [Member] Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] PHP	Dec. 31, 2014 Cash Flow Hedges [Member] Euro / Philippine Peso [Member] Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] PHP	Mar. 31, 2015 Cash Flow Hedges [Member] British Pound / Philippine Peso [Member] Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] PHP	Dec. 31, 2014 Cash Flow Hedges [Member] British Pound / Philippine Peso [Member] Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] PHP	Mar. 31, 2015 Cash Flow Hedges [Member] Euro / U.S. dollar [Member] Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] USD ($)	Dec. 31, 2014 Cash Flow Hedges [Member] Euro / U.S. dollar [Member] Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] USD ($)	Mar. 31, 2015 Cash Flow Hedges [Member] U.S. Dollar / Canadian Dollar [Member] Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] USD ($)	Dec. 31, 2014 Cash Flow Hedges [Member] U.S. Dollar / Canadian Dollar [Member] Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] USD ($)	Dec. 31, 2014 Foreign Currency Hedges [Member] Euro / British Pound [Member] Not Designated as Hedging [Member] Sell/Buy - Sell Notional [Member] EUR (€)	Mar. 31, 2015 Foreign Currency Hedges [Member] Euro / U.S. dollar [Member] Not Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] USD ($)	Dec. 31, 2014 Foreign Currency Hedges [Member] U.S Dollar / Euro [Member] Not Designated as Hedging [Member] Sell/Buy - Sell Notional [Member] USD ($)	Mar. 31, 2015 Foreign Currency Hedges [Member] U.S. Dollar / British Pound [Member] Not Designated as Hedging [Member] Sell/Buy - Sell Notional [Member] USD ($)	Dec. 31, 2014 Foreign Currency Hedges [Member] U.S. Dollar / British Pound [Member] Not Designated as Hedging [Member] Sell/Buy - Sell Notional [Member] USD ($)	Mar. 31, 2015 Foreign Currency Hedges [Member] British Pound / U.S. dollar [Member] Not Designated as Hedging [Member] Sell/Buy - Sell Notional [Member] GBP (£)	Mar. 31, 2015 Foreign Currency Hedges [Member] Euro/ British Pound [Member] Not Designated as Hedging [Member] Sell/Buy - Sell Notional [Member] GBP (£)	Mar. 31, 2015 Foreign Currency Hedges [Member] Euro/ British Pound [Member] Not Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] EUR (€)	Dec. 31, 2014 Foreign Currency Hedges [Member] Euro/ British Pound [Member] Not Designated as Hedging [Member] Sell/Buy - Buy Notional [Member] EUR (€)
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative notional amount	€ 6,236,000	€ 4,592,000	528,553,000	523,313,000	336,235,000	260,535,000	$ 41,796,000	$ 32,527,000	$ 12,999,000	$ 10,036,000	€ 2,000,000	$ 3,000,000	$ 4,000,000	$ 9,000,000	$ 9,000,000	£ 4,000,000	£ 2,000,000	€ 6,000,000	€ 3,000,000