Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Fair Value Disclosures [Abstract]
Net gain from change in fair value of mortgage loans	$ 3.2	$ 2.3

Net Gains Losses From Change In Fair Value Of Mortgages Loans Held For Sale

No definition available.

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