Debt and Derivative Instruments (Summary of Interest Rate Swap Contracts Outstanding) (Details) $ in Thousands | 3 Months Ended |
Mar. 31, 2019USD ($) |
Derivative [Line Items] | | |
Derivative instrument, notional amount | $ 226,244 | |
Derivative instrument, notional amount | 176,000 | |
Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative assets measured on recurring basis | 4,577 | |
Fair value of derivative liabilities measured on recurring basis | $ (3,738) | |
Interest Rate Swap One [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Feb. 11, 2015 | |
Derivative instrument, effective date | Mar. 2, 2015 | |
Derivative instrument, maturity date | Mar. 1, 2022 | |
Derivative instrument, pay fixed interest rate | 2.02% | [1] |
Derivative instrument, notional amount | $ 6,114 | |
Interest Rate Swap One [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative assets measured on recurring basis | $ 26 | |
Interest Rate Swap Two [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Apr. 7, 2015 | |
Derivative instrument, effective date | Apr. 7, 2015 | |
Derivative instrument, maturity date | Apr. 7, 2022 | |
Derivative instrument, pay fixed interest rate | 1.74% | [1] |
Derivative instrument, notional amount | $ 49,400 | |
Interest Rate Swap Two [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative assets measured on recurring basis | $ 608 | |
Interest Rate Swap Three [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Sep. 17, 2015 | |
Derivative instrument, effective date | Sep. 17, 2015 | |
Derivative instrument, maturity date | Sep. 17, 2022 | |
Derivative instrument, pay fixed interest rate | 1.90% | [1] |
Derivative instrument, notional amount | $ 13,700 | |
Interest Rate Swap Three [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative assets measured on recurring basis | $ 118 | |
Interest Rate Swap Four [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Oct. 2, 2015 | |
Derivative instrument, effective date | Nov. 1, 2015 | |
Derivative instrument, maturity date | Nov. 1, 2022 | |
Derivative instrument, pay fixed interest rate | 1.79% | [1] |
Derivative instrument, notional amount | $ 13,100 | |
Interest Rate Swap Four [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative assets measured on recurring basis | $ 163 | |
Interest Rate Swap Five [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Jan. 25, 2016 | |
Derivative instrument, effective date | Feb. 1, 2016 | |
Derivative instrument, maturity date | Feb. 1, 2021 | |
Derivative instrument, pay fixed interest rate | 1.40% | [1] |
Derivative instrument, notional amount | $ 38,000 | |
Interest Rate Swap Five [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative assets measured on recurring basis | $ 586 | |
Interest Rate Swap Six [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Jun. 7, 2016 | |
Derivative instrument, effective date | Jul. 1, 2016 | |
Derivative instrument, maturity date | Jul. 1, 2023 | |
Derivative instrument, pay fixed interest rate | 1.42% | [1] |
Derivative instrument, notional amount | $ 43,680 | |
Interest Rate Swap Six [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative assets measured on recurring basis | $ 1,285 | |
Interest Rate Swap Seven [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Jul. 21, 2016 | |
Derivative instrument, effective date | Aug. 1, 2016 | |
Derivative instrument, maturity date | Aug. 1, 2023 | |
Derivative instrument, pay fixed interest rate | 1.30% | [1] |
Derivative instrument, notional amount | $ 47,550 | |
Interest Rate Swap Seven [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative assets measured on recurring basis | $ 1,676 | |
Interest Rate Swap Eight [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Jun. 5, 2017 | |
Derivative instrument, effective date | May 31, 2017 | |
Derivative instrument, maturity date | May 15, 2022 | |
Derivative instrument, pay fixed interest rate | 1.90% | [1] |
Derivative instrument, notional amount | $ 14,700 | |
Interest Rate Swap Eight [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative assets measured on recurring basis | $ 115 | |
Interest Rate Swap Nine [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Dec. 23, 2015 | |
Derivative instrument, effective date | Dec. 23, 2015 | |
Derivative instrument, maturity date | Jan. 2, 2026 | |
Derivative instrument, pay fixed interest rate | 2.30% | [1] |
Derivative instrument, notional amount | $ 26,000 | |
Interest Rate Swap Nine [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative liabilities measured on recurring basis | $ (175) | |
Interest Rate Swap Ten [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Aug. 23, 2018 | |
Derivative instrument, effective date | Sep. 4, 2018 | |
Derivative instrument, maturity date | Aug. 1, 2023 | |
Derivative instrument, pay fixed interest rate | 2.73% | [1] |
Derivative instrument, notional amount | $ 60,000 | |
Interest Rate Swap Ten [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative liabilities measured on recurring basis | $ (1,423) | |
Interest Rate Swap Eleven [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Aug. 23, 2018 | |
Derivative instrument, effective date | Sep. 4, 2018 | |
Derivative instrument, maturity date | Aug. 1, 2023 | |
Derivative instrument, pay fixed interest rate | 2.74% | [1] |
Derivative instrument, notional amount | $ 25,000 | |
Interest Rate Swap Eleven [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative liabilities measured on recurring basis | $ (593) | |
Interest Rate Swap Twelve [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Aug. 23, 2018 | |
Derivative instrument, effective date | Sep. 4, 2018 | |
Derivative instrument, maturity date | Aug. 1, 2023 | |
Derivative instrument, pay fixed interest rate | 2.74% | [1] |
Derivative instrument, notional amount | $ 25,000 | |
Interest Rate Swap Twelve [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative liabilities measured on recurring basis | $ (598) | |
Interest Rate Swap Thirteen [Member] | | |
Derivative [Line Items] | | |
Derivative instrument, date entered | Aug. 23, 2018 | |
Derivative instrument, effective date | Sep. 4, 2018 | |
Derivative instrument, maturity date | Aug. 1, 2023 | |
Derivative instrument, pay fixed interest rate | 2.73% | [1] |
Derivative instrument, notional amount | $ 40,000 | |
Interest Rate Swap Thirteen [Member] | Recurring [Member] | | |
Derivative [Line Items] | | |
Fair value of derivative liabilities measured on recurring basis | $ (949) | |
|
[1] | Receive floating rate index based upon 1 month LIBOR. At March 31, 2019, the 1 month LIBOR was 2.49%. |