Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Condensed Consolidated Statements of Cash Flows
Net cash provided by operating activities	$ 85,894	$ 81,736
Cash Flows from Investing Activities
Investments purchased	(422,287)	(358,510)
Investments sold	285,886	221,133
Investments called or matured	77,611	114,929
Net change in short-term investments	40,027	10,869
Net property and equipment purchased	(5,543)	(10,766)
Investment in equity method investee	(5,301)
Net cash used in investing activities	(29,607)	(22,345)
Cash Flows from Financing Activities
Cash dividends paid	(22,791)	(21,354)
Stock plan share issuance	3,672	159
Excess tax benefit from exercise of stock options	400	4,888
Net cash used in financing activities	(18,719)	(16,307)
Net increase in cash	37,568	43,084
Cash at the beginning of the period	39,469	44,314
Cash at September 30	$ 77,037	$ 87,398