Derivative Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Derivative [Line Items]
Estimated amount reclassified from accumulated other comprehensive income into income	$ 1,460
Zero Cost Collar and Forward Contracts [Member] | Nomura Financial Investment (Korea) Co., Ltd. [Member]
Derivative [Line Items]
Threshold amount of cash collateral	500
Cash collateral for credit exposure in derivatives	760
Termination provisions for cash and cash equivalents	$ 30,000
Zero Cost Collar and Forward Contracts [Member] | Standard Chartered Bank Korea Limited [Member]
Derivative [Line Items]
Cash collateral for credit exposure in derivatives		$ 1,300