Changes in Accumulated Other Comprehensive Income Balances (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Begining Balance	$ 7,899
Other comprehensive income:
Change in net actuarial loss (see Note 15)	123	120
Tax effect on change in net actuarial loss	(43)	(42)
Net unrealized holding gains arising during the period	9,531	2,024
Tax effect on unrealized gains arising during the period	(3,336)	(709)
Reclassification adjustment for losses included in net realized gains (losses)	(1,809)	101
Tax effect on reclassification adjustment for gains and losses included in income tax expense	633	(35)
Other comprehensive income , net of tax	5,099	1,459
Ending Balance	12,998
Minimum Pension Liability [Member]
Begining Balance	(2,954)	(2,978)
Other comprehensive income:
Change in net actuarial loss (see Note 15)	123	120
Tax effect on change in net actuarial loss	(43)	(42)
Net unrealized holding gains arising during the period	0	0
Tax effect on unrealized gains arising during the period	0	0
Reclassification adjustment for losses included in net realized gains (losses)	0	0
Tax effect on reclassification adjustment for gains and losses included in income tax expense	0	0
Other comprehensive income , net of tax	80	78
Ending Balance	(2,874)	(2,900)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Begining Balance	10,853	9,424
Other comprehensive income:
Change in net actuarial loss (see Note 15)	0	0
Tax effect on change in net actuarial loss	0	0
Net unrealized holding gains arising during the period	9,531	2,024
Tax effect on unrealized gains arising during the period	(3,336)	(709)
Reclassification adjustment for losses included in net realized gains (losses)	(1,809)	101
Tax effect on reclassification adjustment for gains and losses included in income tax expense	633	(35)
Other comprehensive income , net of tax	5,019	1,381
Ending Balance	15,872	10,805
Accumulated Other Comprehensive Income (Loss) [Member]
Begining Balance	7,899	6,446
Other comprehensive income:
Change in net actuarial loss (see Note 15)	123	120
Tax effect on change in net actuarial loss	(43)	(42)
Net unrealized holding gains arising during the period	9,531	2,024
Tax effect on unrealized gains arising during the period	(3,336)	(709)
Reclassification adjustment for losses included in net realized gains (losses)	(1,809)	101
Tax effect on reclassification adjustment for gains and losses included in income tax expense	633	(35)
Other comprehensive income , net of tax	5,099	1,459
Ending Balance	$ 12,998	$ 7,905