Stockholder's/Shareholder's Equity - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jul. 31, 2015	Jul. 31, 2014	Nov. 30, 2004	Nov. 30, 2003
Stockholders Equity [Line Items]
Stock repurchased during period	2,951,243	2,951,243
Payment for repurchase of common stock	$ 24,919,000	$ 24,919,000
Stock Repurchase Program [Member]
Stockholders Equity [Line Items]
Repurchases of common stock				$ 26,000,000	$ 20,000,000	$ 10,000,000	$ 10,000,000
Stock repurchased during period	2,931,125
Payment for repurchase of common stock	$ 24,587,000
Stock purchased during period	0	0	0
Shares remain authorized for repurchase amount	$ 22,874,509