Loans and the Allowance for Loan Losses (Details 11) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012		Mar. 31, 2013		Mar. 31, 2012
Allowance for loan losses:
Beginning balance					$ 44,347		$ 44,340		$ 47,034		$ 44,779
Charge-offs	(3,326)		(6,170)		(8,344)		(16,022)
Recoveries	242		835		1,897		1,626
Net charge-offs	(3,084)		(5,335)		(6,447)		(14,396)
Provision for loan losses	2,768		5,967		9,652		20,905
Benefit attributable to FDIC loss-share agreements	(522)		(1,582)		(2,193)		(7,753)
Recoveries payable to FDIC	54		240		891		973
Provision for loan losses charged to operations	2,300		4,625		8,350		14,125
Ending balance	46,250		44,069		46,250		44,069		47,034		44,779
Period-End Amount Allocated to:
Individually evaluated for impairment	14,908		19,169		14,908		19,169
Collectively evaluated for impairment	31,342		24,900		31,342		24,900
Acquired with deteriorated credit quality	0		0		0		0
Ending balance	46,250		44,069		46,250		44,069		47,034		44,779
Commercial [Member]
Allowance for loan losses:
Beginning balance					3,307		4,197		3,478		3,235
Charge-offs	(887)		(2,590)		(1,167)		(4,623)
Recoveries	54		145		301		323
Net charge-offs	(833)		(2,445)		(866)		(4,300)
Provision for loan losses	364		2,795		874		4,052
Benefit attributable to FDIC loss-share agreements	(67)		(335)		(397)		(723)
Recoveries payable to FDIC	5		2		29		26
Provision for loan losses charged to operations	302		2,462		506		3,355
Ending balance	2,947		3,252		2,947		3,252		3,478		3,235
Period-End Amount Allocated to:
Individually evaluated for impairment	260		715		260		715
Collectively evaluated for impairment	2,687		2,537		2,687		2,537
Acquired with deteriorated credit quality	0		0		0		0
Ending balance	2,947		3,252		2,947		3,252		3,478		3,235
Real Estate - Construction [Member]
Allowance for loan losses:
Beginning balance					711		1,073		863		966
Charge-offs	0		0		0		(42)
Recoveries	7		3		70		6
Net charge-offs	7		3		70		(36)
Provision for loan losses	44		79		132		28
Benefit attributable to FDIC loss-share agreements	0		0		0		(17)
Recoveries payable to FDIC	0		0		1		0
Provision for loan losses charged to operations	44		79		133		11
Ending balance	914		1,048		914		1,048		863		966
Period-End Amount Allocated to:
Individually evaluated for impairment	0		2		0		2
Collectively evaluated for impairment	914		1,046		914		1,046
Acquired with deteriorated credit quality	0		0		0		0
Ending balance	914		1,048		914		1,048		863		966
Real Estate - 1-4 Family Mortgage [Member]
Allowance for loan losses:
Beginning balance					18,347		17,191		19,432		18,980
Charge-offs	(1,251)		(2,682)		(2,517)		(7,230)
Recoveries	120		648		591		981
Net charge-offs	(1,131)		(2,034)		(1,926)		(6,249)
Provision for loan losses	370		2,269		2,088		10,269
Benefit attributable to FDIC loss-share agreements	(326)		(1,187)		(956)		(3,421)
Recoveries payable to FDIC	45		162		837		400
Provision for loan losses charged to operations	89		1,244		1,969		7,248
Ending balance	18,390		18,190		18,390		18,190		19,432		18,980
Period-End Amount Allocated to:
Individually evaluated for impairment	7,569		10,011		7,569		10,011
Collectively evaluated for impairment	10,821		8,179		10,821		8,179
Acquired with deteriorated credit quality	0		0		0		0
Ending balance	18,390		18,190		18,390		18,190		19,432		18,980
Real estate - commercial mortgage [Member]
Allowance for loan losses:
Beginning balance					21,416		20,979		22,239		20,765
Charge-offs	(1,106)		(780)		(4,226)		(3,806)
Recoveries	38		22		885		247
Net charge-offs	(1,068)		(758)		(3,341)		(3,559)
Provision for loan losses	1,975		988		5,762		6,640
Benefit attributable to FDIC loss-share agreements	(129)		(60)		(840)		(3,592)
Recoveries payable to FDIC	4		76		24		543
Provision for loan losses charged to operations	1,850		1,004		4,946		3,591
Ending balance	23,021		21,011		23,021		21,011		22,239		20,765
Period-End Amount Allocated to:
Individually evaluated for impairment	7,079		8,441		7,079		8,441
Collectively evaluated for impairment	15,942		12,570		15,942		12,570
Acquired with deteriorated credit quality	0		0		0		0
Ending balance	23,021		21,011		23,021		21,011		22,239		20,765
Installment and Other [Member]
Allowance for loan losses:
Beginning balance					566	[1]	900	[1]	1,022	[1]	833	[1]
Charge-offs	(82)	[1]	(118)	[1]	(434)	[1]	(321)	[1]
Recoveries	23	[1]	17	[1]	50	[1]	69	[1]
Net charge-offs	(59)	[1]	(101)	[1]	(384)	[1]	(252)	[1]
Provision for loan losses	15	[1]	(164)	[1]	796		(84)	[1]
Benefit attributable to FDIC loss-share agreements	0	[1]	0	[1]	0	[1]	0	[1]
Recoveries payable to FDIC	0	[1]	0	[1]	0	[1]	4	[1]
Provision for loan losses charged to operations	15	[1]	(164)	[1]	796	[1]	(80)	[1]
Ending balance	978	[1]	568	[1]	978	[1]	568	[1]	1,022	[1]	833	[1]
Period-End Amount Allocated to:
Individually evaluated for impairment	0	[1]	0	[1]	0	[1]	0	[1]
Collectively evaluated for impairment	978	[1]	568	[1]	978	[1]	568	[1]
Acquired with deteriorated credit quality	0	[1]	0	[1]	0	[1]	0	[1]
Ending balance	$ 978	[1]	$ 568	[1]	$ 978	[1]	$ 568	[1]	$ 1,022	[1]	$ 833	[1]

[1] Includes lease financing receivables.