Other Liabilities - Components of Other Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Other Liabilities Disclosure [Abstract]
Deferred compensation	$ 6,343	$ 6,725
Pension liability	26,898	26,182
Joint beneficiary agreements	2,640	2,529
Low income housing tax credit fund commitments	15,854	3,330
Accrued salaries and benefits expense	5,177	3,851
Taxes Payable	1,987
Loan escrow and servicing payable	3,393	2,037
Deferred revenue	791	1,082
Unsettled investment security purchases		17,072
Litigation contingent liability reserve	1,450
Miscellaneous other liabilities	5,162	2,485
Total other liabilities	$ 69,695	$ 65,293