Aging of Recorded Investment in Past Due Loans and Leases (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	$ 36,541	$ 50,975
60-89 Days Past due, total	13,083	17,238
Financing Receivable, Greater than 90 Days Past Due	28,529	25,646
Financing Receivable, Total Past Due	78,153	93,859
Current, total	2,318,842	2,352,252
Total ending loan balances	2,396,995	2,446,111	1,627,272
Real estate 1-4 family first mortgage
Aging of Principal Balances in Past Due Loans [Line Items]
Total ending loan balances	1,158,863		1,009,092
HELOC, home equity loans, and other consumer credit
Aging of Principal Balances in Past Due Loans [Line Items]
Total ending loan balances	122,763		21,956
Commercial and industrial
Aging of Principal Balances in Past Due Loans [Line Items]
Total ending loan balances	299,184		79,345
Multi-family
Aging of Principal Balances in Past Due Loans [Line Items]
Total ending loan balances	155,382		126,503
SBA
Aging of Principal Balances in Past Due Loans [Line Items]
Total ending loan balances	26,541		35,662
Construction
Aging of Principal Balances in Past Due Loans [Line Items]
Total ending loan balances	25,144		6,831
Non Traditional Mortgages
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	4,075	1,656
60-89 Days Past due, total	1,783	1,854
Financing Receivable, Greater than 90 Days Past Due	2,263	1,206
Financing Receivable, Total Past Due	8,121	4,716
Current, total	261,289	304,881
Total ending loan balances	269,410	309,597
Non Traditional Mortgages | Real estate 1-4 family first mortgage
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	1,932	1,003
60-89 Days Past due, total	1,670	1,854
Financing Receivable, Greater than 90 Days Past Due	1,826	769
Financing Receivable, Total Past Due	5,428	3,626
Current, total	115,240	152,864
Total ending loan balances	120,668	156,490
Non Traditional Mortgages | Heloc First Liens
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	2,143	653
Financing Receivable, Greater than 90 Days Past Due	437	437
Financing Receivable, Total Past Due	2,580	1,090
Current, total	141,128	146,615
Total ending loan balances	143,708	147,705
Non Traditional Mortgages | Heloc Second Liens
Aging of Principal Balances in Past Due Loans [Line Items]
Current, total	4,921	5,289
Total ending loan balances	4,921	5,289
Non Traditional Mortgages | HELOC, home equity loans, and other consumer credit
Aging of Principal Balances in Past Due Loans [Line Items]
60-89 Days Past due, total	113
Financing Receivable, Total Past Due	113
Current, total		113
Total ending loan balances	113	113
Traditional Loans
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	16,959	27,386
60-89 Days Past due, total	6,909	6,803
Financing Receivable, Greater than 90 Days Past Due	14,156	12,235
Financing Receivable, Total Past Due	38,024	46,424
Current, total	1,776,138	1,750,804
Total ending loan balances	1,814,162	1,797,228
Traditional Loans | Commercial Loan | Commercial and industrial
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	697	52
60-89 Days Past due, total		235
Financing Receivable, Greater than 90 Days Past Due	274
Financing Receivable, Total Past Due	971	287
Current, total	296,675	283,456
Total ending loan balances	297,646	283,743
Traditional Loans | Commercial Loan | Real estate mortgage
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total		5,554
60-89 Days Past due, total		194
Financing Receivable, Total Past Due		5,748
Current, total	545,968	509,121
Total ending loan balances	545,968	514,869
Traditional Loans | Commercial Loan | Multi-family
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	1,016	602
60-89 Days Past due, total	142
Financing Receivable, Greater than 90 Days Past Due	3
Financing Receivable, Total Past Due	1,161	602
Current, total	154,221	140,978
Total ending loan balances	155,382	141,580
Traditional Loans | Commercial Loan | SBA
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	15	14
60-89 Days Past due, total		48
Financing Receivable, Greater than 90 Days Past Due	47
Financing Receivable, Total Past Due	62	62
Current, total	23,002	23,678
Total ending loan balances	23,064	23,740
Traditional Loans | Commercial Loan | Construction
Aging of Principal Balances in Past Due Loans [Line Items]
Current, total	25,144	24,933
Total ending loan balances	25,144	24,933
Traditional Loans | Commercial Loan | Leases financing
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	275	271
60-89 Days Past due, total	69	92
Financing Receivable, Greater than 90 Days Past Due	119	19
Financing Receivable, Total Past Due	463	382
Current, total	48,074	31,567
Total ending loan balances	48,537	31,949
Traditional Loans | Consumer Loan | Real estate 1-4 family first mortgage
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	14,902	20,684
60-89 Days Past due, total	6,698	6,124
Financing Receivable, Greater than 90 Days Past Due	13,677	12,181
Financing Receivable, Total Past Due	35,277	38,989
Current, total	567,171	628,537
Total ending loan balances	602,448	667,526
Traditional Loans | Consumer Loan | HELOC, home equity loans, and other consumer credit
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	54	209
60-89 Days Past due, total		110
Financing Receivable, Greater than 90 Days Past Due	36	35
Financing Receivable, Total Past Due	90	354
Current, total	115,883	108,534
Total ending loan balances	115,973	108,888
Purchased loans
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	15,507	21,933
60-89 Days Past due, total	4,391	8,581
Financing Receivable, Greater than 90 Days Past Due	12,110	12,205
Financing Receivable, Total Past Due	32,008	42,719
Current, total	281,415	296,567
Total ending loan balances	313,423	339,286
Purchased loans | Commercial Loan | Commercial and industrial
Aging of Principal Balances in Past Due Loans [Line Items]
Current, total	1,538	4,028
Total ending loan balances	1,538	4,028
Purchased loans | Commercial Loan | Real estate mortgage
Aging of Principal Balances in Past Due Loans [Line Items]
Financing Receivable, Greater than 90 Days Past Due	880
Financing Receivable, Total Past Due	880
Current, total	13,733	15,014
Total ending loan balances	14,613	15,014
Purchased loans | Commercial Loan | SBA
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	274	45
60-89 Days Past due, total		1
Financing Receivable, Greater than 90 Days Past Due	43	106
Financing Receivable, Total Past Due	317	152
Current, total	3,160	3,536
Total ending loan balances	3,477	3,688
Purchased loans | Consumer Loan | Real estate 1-4 family first mortgage
Aging of Principal Balances in Past Due Loans [Line Items]
30-59 Days Past Due, total	15,233	21,888
60-89 Days Past due, total	4,391	8,580
Financing Receivable, Greater than 90 Days Past Due	11,187	12,099
Financing Receivable, Total Past Due	30,811	42,567
Current, total	261,228	272,253
Total ending loan balances	292,039	314,820
Purchased loans | Consumer Loan | HELOC, home equity loans, and other consumer credit
Aging of Principal Balances in Past Due Loans [Line Items]
Current, total	1,756	1,736
Total ending loan balances	$ 1,756	$ 1,736