Derivative Financial Instruments - Fair Value of Derivative Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Total Asset Derivatives	$ 2,424	$ 1,655
Total Liability Derivatives	4,923	4,547
Derivatives Designated as Hedging Instruments [Member]
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Total Asset Derivatives	1,782	1,208
Total Liability Derivatives	4,923	4,547
Derivatives Designated as Hedging Instruments [Member] | Interest Rate Contracts One [Member] | Other Liabilities [Member]
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Total Liability Derivatives	1,782	1,208
Derivatives Designated as Hedging Instruments [Member] | Interest Rate Contracts Two [Member] | Other Liabilities [Member]
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Total Liability Derivatives	3,141	3,339
Derivatives Designated as Hedging Instruments [Member] | Interest Rate Contracts Two [Member] | Other Assets [Member]
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Total Asset Derivatives	1,782	1,208
Derivatives Not Designated as Hedging Instruments [Member]
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Total Asset Derivatives	642	447
Derivatives Not Designated as Hedging Instruments [Member] | Mortgage Loan Contracts [Member] | Other Assets [Member]
Fair Values Of Financial Assets And Liabilities Including Derivative Financial Instruments [Line Items]
Total Asset Derivatives	$ 642	$ 447