Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Statement Of Financial Position [Abstract]
Amortized cost of investments	$ 128,185	$ 126,873
Allowance for premiums and fees receivable	$ 310	$ 311
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000	10,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	75,000	75,000
Common stock, shares issued	40,981	40,981
Common stock, shares outstanding	40,983	40,983