Unaudited Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Unaudited Consolidated Statements of Cash Flows [Abstract]
Net cash provided by operating activities	$ 22,445	$ 26,769
Investing activities:
Purchases of available-for-sale investments	(165,890)	(182,133)
Purchases of limited partnership interests	(1,538)	0
Proceeds from sales or maturities of available-for-sale investments	147,345	188,102
Net sales (purchases) of short-term investments	329	(83)
Other investing activities	2,701	(868)
Net cash provided by (used in) investing activities	(17,053)	5,018
Financing activities:
Dividends paid to shareholders	(7,474)	(7,454)
Repayment on line of credit	0	(5,000)
Net cash used in financing activities	(7,474)	(12,454)
Effect of foreign exchange rates on cash and cash equivalents	(19)	288
Increase (decrease) in cash and cash equivalents	(2,101)	19,621
Cash and cash equivalents at beginning of period	89,726	38,223
Cash and cash equivalents at end of period	$ 87,625	$ 57,844