Aggregate Contractual or Notional Amounts and Fair Value of Derivative Financial Instruments (Detail) - USD ($) |
Sep. 30, 2016 |
Dec. 31, 2015 |
Mar. 31, 2015 |
Feb. 28, 2014 |
|---|---|---|---|---|
| Derivative [Line Items] | ||||
| Notional or Contractual Amount | $ 4,944,000 | $ 5,151,000 | ||
| Derivative Assets | 0 | 0 | ||
| Derivative Liabilities | 450,000 | 251,000 | ||
| Interest Rate Swaps Agreement | ||||
| Derivative [Line Items] | ||||
| Notional or Contractual Amount | $ 1,200,000 | $ 4,370,000 | ||
| Interest Rate Swaps Agreement | Designated as Hedging Instrument | ||||
| Derivative [Line Items] | ||||
| Notional or Contractual Amount | 4,944,000 | 5,151,000 | ||
| Derivative Assets | 0 | 0 | ||
| Derivative Liabilities | $ 450,000 | $ 251,000 |