Netting of Financial Instruments - Summary of Derivative Assets and Collateral Held by Counterparty (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Derivative assets, Fair value, Total	$ 18,462	$ 10,085
Financial instruments	0	0
Cash collateral received	0	0
Net amount	18,462	10,085
Interest Rate Lock Commitments [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	9,372	4,983
Financial instruments	0	0
Cash collateral received	0	0
Net amount	9,372	4,983
RJ O'Brien & Associates, LLC [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	2,805	1,672
Financial instruments	0	0
Cash collateral received	0	0
Net amount	2,805	1,672
Fannie Mae Capital Markets [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	2,466	0
Financial instruments	0	0
Cash collateral received	0	0
Net amount	2,466	0
Bank of America, N.A. [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	1,220	0
Financial instruments	0	0
Cash collateral received	0	0
Net amount	1,220	0
Jefferies Group, LLC [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	726	541
Financial instruments	0	0
Cash collateral received	0	0
Net amount	726	541
BNP Paribas [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	682	59
Financial instruments	0	0
Cash collateral received	0	0
Net amount	682	59
Wells Fargo [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	468	99
Financial instruments	0	0
Cash collateral received	0	0
Net amount	468	99
Nomura Securities International, Inc [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	395	119
Financial instruments	0	0
Cash collateral received	0	0
Net amount	395	119
Barclays Capital [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	0	796
Financial instruments	0	0
Cash collateral received	0	0
Net amount	0	796
Morgan Stanley Bank, N.A. [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	0	464
Financial instruments	0	0
Cash collateral received	0	0
Net amount	0	464
Royal Bank of Canada [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	0	400
Financial instruments	0	0
Cash collateral received	0	0
Net amount	0	400
Ally Financial [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	0	209
Financial instruments	0	0
Cash collateral received	0	0
Net amount	0	209
Other [Member]
Derivative [Line Items]
Derivative assets, Fair value, Total	328	743
Financial instruments	0	0
Cash collateral received	0	0
Net amount	$ 328	$ 743

Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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