Loans (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010
Mortgage loans on real estate:
Total mortgage loan on real estate	$ 984,147		$ 965,922
Consumer:
Total consumer loans	393,248		406,330
Commercial	139,733		139,131
Construction:
Total construction	35,354		39,649
Total loans, net of deferred loan fees	1,552,482		1,551,032
Total principal balance of loans owed-net of charge-offs	1,599,197		1,607,039
Unamortized net deferred loan fees	(2,054)		(2,308)
Discounts to principal balance of loans owed, net of charge-offs	(44,661)		(53,699)
Total loans, net of unamortized deferred loan fees	1,552,482		1,551,032
Noncovered loans	1,509,566		1,501,961
Covered loans	42,916		49,071
Total loans, net of unamortized deferred loan fees	1,552,482		1,551,032
Allowance for loan losses	(45,849)	(45,452)	(45,914)	(43,962)	(43,224)	(42,571)
Auto Indirect [Member]
Consumer:
Total consumer loans	6,496		10,821
Other [Member]
Consumer:
Total consumer loans	25,561		23,360
Home equity lines of credit [Member]
Consumer:
Total consumer loans	346,917		357,305
Home equity loans [Member]
Consumer:
Total consumer loans	14,274		14,844
Residential [Member]
Construction:
Total construction	19,259		22,122
Commercial [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	850,132		826,336
Construction:
Total construction	16,095		17,527
Residential 1-4 family [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	134,015		139,586
Originated [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	860,287		818,002
Consumer:
Total consumer loans	357,665		367,245
Commercial	127,123		123,486
Construction:
Total construction	23,180		26,652
Total loans, net of deferred loan fees	1,368,255		1,335,385
Total principal balance of loans owed-net of charge-offs	1,370,309		1,337,693
Unamortized net deferred loan fees	(2,054)		(2,308)
Discounts to principal balance of loans owed, net of charge-offs
Total loans, net of unamortized deferred loan fees	1,368,255		1,335,385
Noncovered loans	1,368,255		1,335,385
Covered loans
Total loans, net of unamortized deferred loan fees	1,368,225		1,335,385
Allowance for loan losses	(40,360)		(41,458)
Originated [Member] | Auto Indirect [Member]
Consumer:
Total consumer loans	6,496		10,821
Originated [Member] | Other [Member]
Consumer:
Total consumer loans	22,670		20,270
Originated [Member] | Home equity lines of credit [Member]
Consumer:
Total consumer loans	314,973		321,834
Originated [Member] | Home equity loans [Member]
Consumer:
Total consumer loans	13,526		14,320
Originated [Member] | Residential [Member]
Construction:
Total construction	10,793		13,908
Originated [Member] | Commercial [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	740,782		699,682
Construction:
Total construction	12,387		12,744
Originated [Member] | Residential 1-4 family [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	119,505		118,320
PNCI [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	85,382		108,178
Consumer:
Total consumer loans	21,390		24,310
Commercial	1,223		1,805
Construction:
Total construction
Total loans, net of deferred loan fees	107,995		134,293
Total principal balance of loans owed-net of charge-offs	123,833		152,549
Unamortized net deferred loan fees
Discounts to principal balance of loans owed, net of charge-offs	(15,838)		(18,256)
Total loans, net of unamortized deferred loan fees	107,995		134,293
Noncovered loans	107,995		134,293
Covered loans
Total loans, net of unamortized deferred loan fees	107,995		134,293
Allowance for loan losses	(402)		(245)
PNCI [Member] | Auto Indirect [Member]
Consumer:
Total consumer loans
PNCI [Member] | Other [Member]
Consumer:
Total consumer loans	2,852		3,041
PNCI [Member] | Home equity lines of credit [Member]
Consumer:
Total consumer loans	17,995		20,902
PNCI [Member] | Home equity loans [Member]
Consumer:
Total consumer loans	543		367
PNCI [Member] | Residential [Member]
Construction:
Total construction
PNCI [Member] | Commercial [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	76,938		93,428
Construction:
Total construction
PNCI [Member] | Residential 1-4 family [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	8,444		14,750
PCI- Cash basis [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	1,136
Consumer:
Total consumer loans	8,271		8,615
Commercial	698		811
Construction:
Total construction
Total loans, net of deferred loan fees	10,105		9,426
Total principal balance of loans owed-net of charge-offs	22,340		22,137
Unamortized net deferred loan fees
Discounts to principal balance of loans owed, net of charge-offs	(12,235)		(12,711)
Total loans, net of unamortized deferred loan fees	10,105		9,426
Noncovered loans	10,105		9,426
Covered loans
Total loans, net of unamortized deferred loan fees	10,105		9,426
Allowance for loan losses	(1,137)		(1,034)
PCI- Cash basis [Member] | Auto Indirect [Member]
Consumer:
Total consumer loans
PCI- Cash basis [Member] | Other [Member]
Consumer:
Total consumer loans
PCI- Cash basis [Member] | Home equity lines of credit [Member]
Consumer:
Total consumer loans	8,222
PCI- Cash basis [Member] | Home equity loans [Member]
Consumer:
Total consumer loans	49
PCI- Cash basis [Member] | Residential [Member]
Construction:
Total construction
PCI- Cash basis [Member] | Commercial [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	1,136
Construction:
Total construction
PCI- Cash basis [Member] | Residential 1-4 family [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate
PCI- Other [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	37,342		39,742
Consumer:
Total consumer loans	5,922		6,160
Commercial	10,689		13,029
Construction:
Total construction	12,174		12,997
Total loans, net of deferred loan fees	66,127		71,928
Total principal balance of loans owed-net of charge-offs	82,715		94,660
Unamortized net deferred loan fees
Discounts to principal balance of loans owed, net of charge-offs	(16,588)		(22,732)
Total loans, net of unamortized deferred loan fees	66,127		71,928
Noncovered loans	23,211		22,857
Covered loans	42,916		49,071
Total loans, net of unamortized deferred loan fees	66,127		71,928
Allowance for loan losses	(3,950)		(3,177)
PCI- Other [Member] | Auto Indirect [Member]
Consumer:
Total consumer loans
PCI- Other [Member] | Other [Member]
Consumer:
Total consumer loans	39		49
PCI- Other [Member] | Home equity lines of credit [Member]
Consumer:
Total consumer loans	5,727		5,954
PCI- Other [Member] | Home equity loans [Member]
Consumer:
Total consumer loans	156		157
PCI- Other [Member] | Residential [Member]
Construction:
Total construction	8,466		8,214
PCI- Other [Member] | Commercial [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	31,276		33,226
Construction:
Total construction	3,708		4,783
PCI- Other [Member] | Residential 1-4 family [Member]
Mortgage loans on real estate:
Total mortgage loan on real estate	$ 6,066		$ 6,516