Derivative Financial Instruments - Additional Information (Detail)	12 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2013 Foreign Exchange Forward And Option Contracts General maturity Upper Limit	Dec. 31, 2013 Foreign Exchange Forward And Option Contracts Extended maturity Upper Limit
Derivative Instruments and Hedging Activities Disclosure [Line Items]
Managing interest rate risk for senior notes and subordinated notes	To manage interest rate risk for our 6.05% Subordinated Notes, we entered into a fixed-for-floating interest rate swap agreement at the time of debt issuance based upon LIBOR with matched-terms.
Contract term		1 year	5 years