Loans and Leases - Age Analysis of Past Due Loans and Leases (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	$ 28,566	$ 17,644
Current	2,149,194	1,608,981
Carrying amount	1,253	0
Loans and leases held for investment	2,179,013	1,626,625
Recorded Investment 90 Days or more Past Due and Accruing Interest	379	451
Valley Green Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount	1,253
Financing Receivables, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	17,632	3,405
Financing Receivables, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	3,524	3,196
Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	7,410	11,043
Commercial, Financial and Agricultural [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	5,441	3,459
Current	498,757	454,368
Carrying amount		0
Loans and leases held for investment	504,515	457,827
Recorded Investment 90 Days or more Past Due and Accruing Interest	0	0
Commercial, Financial and Agricultural [Member] | Valley Green Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount	317
Commercial, Financial and Agricultural [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	864	145
Commercial, Financial and Agricultural [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	298	747
Commercial, Financial and Agricultural [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	4,279	2,567
Real Estate-Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	13,205	2,437
Current	872,174	626,041
Carrying amount		0
Loans and leases held for investment	885,892	628,478
Recorded Investment 90 Days or more Past Due and Accruing Interest	0	0
Real Estate-Commercial [Member] | Valley Green Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount	513
Real Estate-Commercial [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	12,103	361
Real Estate-Commercial [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	0	913
Real Estate-Commercial [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	1,102	1,163
Real Estate-Construction [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	0	5,930
Current	96,541	73,957
Carrying amount		0
Loans and leases held for investment	96,541	79,887
Recorded Investment 90 Days or more Past Due and Accruing Interest	0	0
Real Estate-Construction [Member] | Valley Green Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount	0
Real Estate-Construction [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	0	0
Real Estate-Construction [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	0	405
Real Estate-Construction [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	0	5,525
Real Estate-Residential Secured for Business Purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	4,489	936
Current	213,871	35,996
Carrying amount		0
Loans and leases held for investment	218,783	36,932
Recorded Investment 90 Days or more Past Due and Accruing Interest	0	0
Real Estate-Residential Secured for Business Purpose [Member] | Valley Green Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount	423
Real Estate-Residential Secured for Business Purpose [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	1,406	167
Real Estate-Residential Secured for Business Purpose [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	2,356	56
Real Estate-Residential Secured for Business Purpose [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	727	713
Real Estate-Residential Secured for Personal Purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	1,368	1,073
Current	179,787	165,777
Carrying amount		0
Loans and leases held for investment	181,155	166,850
Recorded Investment 90 Days or more Past Due and Accruing Interest	0	0
Real Estate-Residential Secured for Personal Purpose [Member] | Valley Green Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount	0
Real Estate-Residential Secured for Personal Purpose [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	990	409
Real Estate-Residential Secured for Personal Purpose [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	69	604
Real Estate-Residential Secured for Personal Purpose [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	309	60
Real Estate-Home Equity Secured for Personal Purpose [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	1,003	563
Current	135,952	107,687
Carrying amount		0
Loans and leases held for investment	136,955	108,250
Recorded Investment 90 Days or more Past Due and Accruing Interest	0	31
Real Estate-Home Equity Secured for Personal Purpose [Member] | Valley Green Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount	0
Real Estate-Home Equity Secured for Personal Purpose [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	777	348
Real Estate-Home Equity Secured for Personal Purpose [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	52	0
Real Estate-Home Equity Secured for Personal Purpose [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	174	215
Loans to Individuals [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	468	795
Current	29,264	29,146
Carrying amount		0
Loans and leases held for investment	29,732	29,941
Recorded Investment 90 Days or more Past Due and Accruing Interest	173	365
Loans to Individuals [Member] | Valley Green Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount	0
Loans to Individuals [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	198	365
Loans to Individuals [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	97	65
Loans to Individuals [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	173	365
Lease Financings [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	2,592	2,451
Current	122,848	116,009
Carrying amount		0
Loans and leases held for investment	125,440	118,460
Recorded Investment 90 Days or more Past Due and Accruing Interest	206	55
Lease Financings [Member] | Valley Green Bank [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Carrying amount	0
Lease Financings [Member] | Financing Receivables, 30 to 59 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	1,294	1,610
Lease Financings [Member] | Financing Receivables, 60 to 89 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	652	406
Lease Financings [Member] | Financing Receivables, Equal to Greater than 90 Days Past Due [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Past Due	$ 646	$ 435