Assets Acquired In FDIC-Assisted Acquisitions (Components Of Covered Assets) (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2011
Covered loans	$ 778,746	$ 739,190	$ 649,001
Less: Credit risk adjustments	175,820	166,107	160,349
Less: Liquidity and rate adjustments	1,189	1,594	2,163
Total covered loans	601,737	571,489	486,489
OREO	104,177	101,685	76,648
Less: Fair value adjustments	20,710	23,068	13,065
Total covered OREO	83,467	78,617	63,583
Total covered assets	685,204	650,106	550,072
FDIC indemnification asset	203,801	242,394	160,927
American United Bank (AUB)
Covered loans	29,740	34,242	48,309
Less: Credit risk adjustments	2,542	3,236	5,208
Less: Liquidity and rate adjustments			86
Total covered loans	27,198	31,006	43,015
OREO	11,489	11,100	11,064
Less: Fair value adjustments			77
Total covered OREO	11,489	11,100	10,987
Total covered assets	38,687	42,106	54,002
FDIC indemnification asset	2,620	7,271	5,338
United Security Bank (USB)
Covered loans	40,355	51,409	67,203
Less: Credit risk adjustments	4,666	5,259	6,332
Less: Liquidity and rate adjustments		50	249
Total covered loans	35,689	46,100	60,622
OREO	7,192	7,445	10,274
Less: Fair value adjustments	50	50	73
Total covered OREO	7,142	7,395	10,201
Total covered assets	42,831	53,495	70,823
FDIC indemnification asset	6,757	10,648	9,888
Satilla Community Bank (SCB)
Covered loans	46,033	56,780	61,958
Less: Credit risk adjustments	840	5,779	6,471
Less: Liquidity and rate adjustments		155	361
Total covered loans	45,193	50,846	55,126
OREO	11,078	10,635	9,761
Less: Fair value adjustments	646	500	500
Total covered OREO	10,432	10,135	9,261
Total covered assets	55,625	60,981	64,387
FDIC indemnification asset	4,663	6,527	9,669
First Bank of Jacksonville (FBJ)
Covered loans	35,618	40,106	45,011
Less: Credit risk adjustments	6,645	7,473	8,500
Less: Liquidity and rate adjustments	59	92	119
Total covered loans	28,914	32,541	36,392
OREO	2,787	2,370	3,053
Less: Fair value adjustments	515	641	1,559
Total covered OREO	2,272	1,729	1,494
Total covered assets	31,186	34,270	37,886
FDIC indemnification asset	7,051	8,551	9,812
Darby Bank & Trust (DBT)
Covered loans	222,724	260,883	326,991
Less: Credit risk adjustments	60,218	68,757	112,589
Less: Liquidity and rate adjustments	455	703	951
Total covered loans	162,051	191,423	213,451
OREO	24,121	28,947	36,383
Less: Fair value adjustments	1,422	2,763	9,582
Total covered OREO	22,699	26,184	26,801
Total covered assets	184,750	217,607	240,252
FDIC indemnification asset	65,684	105,528	100,150
Tifton Banking Company (TBC)
Covered loans	63,593	79,586	99,529
Less: Credit risk adjustments	8,155	14,358	21,249
Less: Liquidity and rate adjustments	252	331	397
Total covered loans	55,186	64,897	77,883
OREO	8,616	8,441	6,113
Less: Fair value adjustments	1,184	1,274	1,274
Total covered OREO	7,432	7,167	4,839
Total covered assets	62,618	72,064	82,722
FDIC indemnification asset	14,838	18,628	26,070
High Trust Bank [HTB]
Covered loans	98,624	110,899
Less: Credit risk adjustments	20,676	28,024
Less: Liquidity and rate adjustments	60	73
Total covered loans	77,888	82,802
OREO	16,860	20,132
Less: Fair value adjustments	6,499	10,171
Total covered OREO	10,361	9,961
Total covered assets	88,249	92,763
FDIC indemnification asset	25,249	48,289
One Georgia Bank (OGB)
Covered loans	88,717	105,285
Less: Credit risk adjustments	22,041	33,221
Less: Liquidity and rate adjustments	156	190
Total covered loans	66,520	71,874
OREO	13,397	12,615
Less: Fair value adjustments	6,573	7,669
Total covered OREO	6,824	4,946
Total covered assets	73,344	76,820
FDIC indemnification asset	26,105	36,952
Central Bank of Georgia (CBG)
Covered loans	153,342
Less: Credit risk adjustments	50,037
Less: Liquidity and rate adjustments	207
Total covered loans	103,098
OREO	8,637
Less: Fair value adjustments	3,821
Total covered OREO	4,816
Total covered assets	107,914
FDIC indemnification asset	$ 50,834