CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Unrealized holding gains (losses), taxes	$ (12,130)	$ (44)	$ (11,881)	$ (5)
Reclassification adjustment for (gains) losses included in net income, taxes	(404)	(611)	(3,022)	(1,117)
Unrealized holding gains, tax (expense) benefit	(70)	(425)	(94)	1,510
Reclassification adjustment for (gains) losses included in net income, tax (expense) benefit	$ 45	$ (70)	$ 45	$ 256