Loans Receivable, Net - Recorded Investment in Residential and Consumer Loans Based on Payment Activity (Detail) (Residential Real Estate [Member], USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Originated by Bank [Member]
Financing Receivable, Recorded Investment [Line Items]
Performing	$ 652,851	$ 670,946
Non-performing	14,858	13,156
Total	667,709	684,102
Originated by Mortgage Company [Member]
Financing Receivable, Recorded Investment [Line Items]
Performing	94,246	104,131
Non-performing	10,813	10,477
Total	105,059	114,608
Originated by Mortgage Company - Non-Prime [Member]
Financing Receivable, Recorded Investment [Line Items]
Performing	1,316	1,361
Non-performing	2,774	2,888
Total	4,090	4,249
Residential Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Performing	12,879	9,013
Non-performing
Total	12,879	9,013
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Performing	187,130	193,603
Non-performing	5,195	4,540
Total	$ 192,325	$ 198,143