Acquisition Activity - Schedule of Assets Acquired and Liabilities Assumed (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	May. 31, 2015	Mar. 31, 2015	Feb. 28, 2015
Florida Bank Group, Inc.
Assets
Cash and cash equivalents	$ 72,982			$ 72,982
Investment securities	107,372			107,236
Loans	307,531			312,902
Other real estate owned	423			498
Core deposit intangible	4,489			0
Deferred tax asset, net	26,720			18,151
Other assets	20,868			29,817
Total Assets	540,385			541,586
Liabilities
Interest-bearing deposits	282,680			282,417
Non-interest-bearing deposits	109,548			109,548
Borrowings	68,598			60,000
Other liabilities	6,516			1,898
Total Liabilities	467,342			$ 453,863
Old Florida Bancshares, Inc.
Assets
Cash and cash equivalents	360,688		$ 360,688
Investment securities	67,209		67,209
Loans held for sale	5,952		5,952
Loans	1,062,951		1,073,773
Other real estate owned	5,964		4,515
Core deposit intangible	6,821		0
Deferred tax asset, net	13,878		9,490
Other assets	23,311		30,549
Total Assets	1,546,774		1,552,176
Liabilities
Interest-bearing deposits	1,048,888		1,048,765
Non-interest-bearing deposits	340,869		340,869
Borrowings	1,528		1,528
Other liabilities	3,114		3,038
Total Liabilities	1,394,399		$ 1,394,200
Georgia Commerce Bancshares, Inc.
Assets
Cash and cash equivalents	51,059	$ 51,059
Investment securities	134,904	135,710
Loans held for sale	1,249	1,249
Loans	792,120	807,726
Other real estate owned	5,588	9,795
Core deposit intangible	6,720	0
Deferred tax asset, net	8,348	2,897
Other assets	28,295	28,952
Total Assets	1,028,283	1,037,388
Liabilities
Interest-bearing deposits	658,309	658,133
Non-interest-bearing deposits	249,739	249,739
Borrowings	13,203	13,203
Other liabilities	6,195	6,195
Total Liabilities	927,446	$ 927,270
Preliminary Fair Value Adjustments | Florida Bank Group, Inc.
Assets
Cash and cash equivalents	0
Investment securities	136
Loans	(5,371)
Other real estate owned	(75)
Core deposit intangible	4,489
Deferred tax asset, net	8,569
Other assets	(8,949)
Total Assets	(1,201)
Liabilities
Interest-bearing deposits	263
Non-interest-bearing deposits	0
Borrowings	8,598
Other liabilities	4,618
Total Liabilities	13,479
Preliminary Fair Value Adjustments | Old Florida Bancshares, Inc.
Assets
Cash and cash equivalents	0
Investment securities	0
Loans held for sale	0
Loans	(10,822)
Other real estate owned	1,449
Core deposit intangible	6,821
Deferred tax asset, net	4,388
Other assets	(7,238)
Total Assets	(5,402)
Liabilities
Interest-bearing deposits	123
Non-interest-bearing deposits	0
Borrowings	0
Other liabilities	76
Total Liabilities	199
Preliminary Fair Value Adjustments | Georgia Commerce Bancshares, Inc.
Assets
Cash and cash equivalents	0
Investment securities	(806)
Loans held for sale	0
Loans	(15,606)
Other real estate owned	(4,207)
Core deposit intangible	6,720
Deferred tax asset, net	5,451
Other assets	(657)
Total Assets	(9,105)
Liabilities
Interest-bearing deposits	176
Non-interest-bearing deposits	0
Borrowings	0
Other liabilities	0
Total Liabilities	$ 176