Condensed Consolidated Statements of Cash Flows (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Operating Activities
Net income	$ 11,196	$ 21,701
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	529	516
Net amortization of investments	2,803	2,292
Deferred income taxes	819	(2,575)
Net realized gains on investments	(248)	(2,845)
Share-based compensation	261	464
Changes in operating assets and liabilities:
Premiums receivable, net	(17,842)	(7,015)
Accrued interest receivable	(673)	(461)
Deferred policy acquisition costs and deferred charges	(2,873)	(1,513)
Other assets and federal income tax recoverable	(2,684)	4,534
Reserves for loss and loss adjustment expenses	(5,156)	(2,707)
Unearned premiums	16,955	6,802
Reinsurance balances	1,787	(11,391)
Amounts held for others and policyholder deposits	1,954	1,375
Accounts payable and other liabilities	(2,169)	1,200
Net cash provided by operating activities	4,659	10,377
Investing Activities
Purchases of investments held-to-maturity	(49,416)	(40,601)
Purchases of investments available-for-sale	(43,530)	(13,841)
Purchases of short-term investments	(49,969)	(42,866)
Proceeds from maturities of investments held-to-maturity	61,452	26,344
Proceeds from sales and maturities of investments available-for-sale	13,223	21,924
Proceeds from sales and maturities of short-term investments	65,141	32,467
Purchases of property and equipment	(316)	(1,267)
Net cash used in investing activities	(3,415)	(17,840)
Financing Activities
Proceeds from stock option exercises	1,993	917
Tax benefit from share-based payments	700	134
Treasury shares purchased	(2,859)	(6,638)
Net cash used in financing activities	(166)	(5,587)
Change in cash and cash equivalents	1,078	(13,050)
Cash and cash equivalents at beginning of period	60,966	63,188
Cash and cash equivalents at end of period	$ 62,044	$ 50,138