Consideration Transferred to Acquire Real Estate Properties (Parenthetical) (Detail) - USD ($) $ in Thousands	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Allowance for loan losses	$ 18,237	$ 18,165	$ 17,097	$ 12,796	$ 10,797	$ 9,218
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Allowance for loan losses	$ 1,213