v3.8.0.1

Interest Rate Swaps - Summary of Interest-rate Swap Agreements (Detail) - Interest Rate Swap - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Derivative [Line Items] |  |
Fair Value | $ 5,988,000 | $ (619,000)
Bank of America |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Nov. 30, 2023 |
Derivative, Fixed rate | 2.80% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ (863,000) | (1,338,000)
Bank of Montreal One |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jul. 31, 2024 |
Derivative, Fixed rate | 1.16% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 40,000,000 |
Fair Value | $ 2,503,000 | 2,485,000
Bank of Montreal Two |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jan. 31, 2025 |
Derivative, Fixed rate | 1.91% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ 464,000 | 299,000
Bank of Montreal Three |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jul. 31, 2025 |
Derivative, Fixed rate | 2.32% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ (194,000) | (433,000)
Bank of Montreal Four |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jan. 31, 2026 |
Derivative, Fixed rate | 1.92% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ 561,000 | 437,000
Bank of Montreal Five |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jan. 31, 2026 |
Derivative, Fixed rate | 2.05% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 40,000,000 |
Fair Value | $ 520,000 | 275,000
Bank of Montreal Six |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Dec. 31, 2026 |
Derivative, Fixed rate | 2.33% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 10,000,000 |
Fair Value | $ (63,000) | (132,000)
Bank of Montreal Seven |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Dec. 31, 2027 |
Derivative, Fixed rate | 2.37% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ (192,000) |
Capital One One |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Dec. 31, 2021 |
Derivative, Fixed rate | 1.05% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 15,000,000 |
Fair Value | $ 607,000 | 552,000
Capital One Two |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Dec. 31, 2024 |
Derivative, Fixed rate | 1.58% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 15,000,000 |
Fair Value | $ 603,000 | 565,000
Capital One Three |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jan. 31, 2026 |
Derivative, Fixed rate | 2.08% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 35,000,000 |
Fair Value | $ 399,000 | 216,000
Capital One Four |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jul. 31, 2026 |
Derivative, Fixed rate | 1.32% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 35,000,000 |
Fair Value | $ 2,565,000 | 2,667,000
Capital One Five |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Dec. 31, 2027 |
Derivative, Fixed rate | 2.37% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ (189,000) |
M&T Bank |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Sep. 30, 2017 |
Derivative, Fixed rate | 1.09% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value |  | (37,000)
M&T Bank One |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Apr. 30, 2020 |
Derivative, Fixed rate | 4.91% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 21,335,000 |
Fair Value |  | (2,266,000)
M&T Bank Two |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Aug. 31, 2021 |
Derivative, Fixed rate | 1.02% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 5,183,000 |
Fair Value | $ 182,000 |
M&T Bank Three |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Sep. 30, 2022 |
Derivative, Fixed rate | 2.83% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ (810,000) | (993,000)
M&T Bank Four |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Nov. 30, 2023 |
Derivative, Fixed rate | 2.65% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ (686,000) | (1,102,000)
Regions Bank |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Mar. 31, 2017 |
Derivative, Fixed rate | 0.70% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 50,000,000 |
Fair Value |  | 6,000
Regions Bank One |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Mar. 31, 2018 |
Derivative, Fixed rate | 1.77% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ (9,000) | (179,000)
Regions Bank Two |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Mar. 31, 2019 |
Derivative, Fixed rate | 1.91% |
Variable Rate Index | LIBOR 3 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ 2,000 | (239,000)
Regions Bank Three |  |
Derivative [Line Items] |  |
Derivative, Maturity date | May 31, 2020 |
Derivative, Fixed rate | 2.12% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 50,000,000 |
Fair Value | $ (153,000) | (940,000)
Regions Bank Four |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Mar. 31, 2022 |
Derivative, Fixed rate | 2.43% |
Variable Rate Index | LIBOR 3 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ (254,000) | (594,000)
Regions Bank Five |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Dec. 31, 2023 |
Derivative, Fixed rate | 1.18% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ 1,402,000 | 1,392,000
Sun Trust Bank One |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Apr. 30, 2024 |
Derivative, Fixed rate | 1.99% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ 261,000 | 47,000
Sun Trust Bank Two |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Apr. 30, 2025 |
Derivative, Fixed rate | 2.20% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value |  | (219,000)
Sun Trust Bank Three |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jul. 31, 2025 |
Derivative, Fixed rate | 1.99% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ 386,000 | 228,000
Sun Trust Bank Four |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Dec. 31, 2025 |
Derivative, Fixed rate | 2.30% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ (138,000) |
Sun Trust Bank Five |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jan. 31, 2026 |
Derivative, Fixed rate | 1.93% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 25,000,000 |
Fair Value | $ 553,000 | 429,000
Wells Fargo Bank One |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Feb. 28, 2021 |
Derivative, Fixed rate | 2.39% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 35,000,000 |
Fair Value | $ (369,000) | (1,013,000)
Wells Fargo Bank Two |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Oct. 31, 2024 |
Derivative, Fixed rate | 2.72% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 15,000,000 |
Fair Value | $ (510,000) | $ (732,000)
Wells Fargo Bank Three |  |
Derivative [Line Items] |  |
Derivative, Maturity date | Jan. 31, 2028 |
Derivative, Fixed rate | 2.37% |
Variable Rate Index | LIBOR 1 month |
Notional Amount | $ 75,000,000 |
Fair Value | $ (590,000) |

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