Derivatives - Offsetting Derivative Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gross Amounts Recognized, Derivative Assets	$ 224	$ 650
Gross Amounts Offset in the Statement of Financial Position, Derivative Assets	0	0
Net Amounts Presented in the Statement of Financial Position, Derivative Assets	224	650
Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments, Derivative Assets	224	650
Gross Amounts Not offset in the Statement of Financial Position -Cash Collateral, Derivative Assets	0	0
Net Amount, Derivative Assets	0	0
Gross Amounts Recognized, Derivative Liabilities	21,034	16,771
Gross Amounts Offset in the Statement of Financial Position, Derivative Liabilities	0	0
Net Amounts Presented in the Statement of Financial Position, Derivative Liabilities	21,034	16,771
Gross Amounts Not Offset in the Statement of Financial Position - Financial Instruments, Derivative Liabilities	224	650
Gross Amounts Not offset in the Statement of Financial Position -Cash Collateral, Derivative Liabilities	23,482	17,343
Net Amount, Derivative Liabilities	$ (2,672)	$ (1,222)