Stockholder's Equity - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stockholders' Equity Note [Line Items]
Common stock available for issuance	6,915,000
Options outstanding, Shares	7,131,000	9,036,000	7,365,000
Stock-based compensation expense	$ 73,000	$ 131,000	$ 128,000
Unrecognized stock-based compensation expense	$ 97,000	$ 115,000
Unrecognized stock-based compensation, Recognition period	5 years
Granted to independent agent and employees	150,000	3,425,000
Independent Sales Agents
Stockholders' Equity Note [Line Items]
Granted to independent agent and employees	2,513,000
Seven Stock Option Plans
Stockholders' Equity Note [Line Items]
Common stock available for issuance	18,850,000