| Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] |   |  |  |  |  |  |  |  |  | Unrealized Gains (Losses) on Derivatives Instruments |  |  |  |  |   | Balance June 30, 2016 |  | $ | (5,542 | ) |  |  | (64,863 | ) |  |  | - |  |  | $ | (70,405 | ) |   | Other comprehensive income (loss) before reclassifications |  |  | 24,531 |  |  |  | (3,061 | ) |  |  | - |  |  |  | 21,470 |  |   | Balance June 30, 2017 |  | $ | 18,989 |  |  |  | (67,924 | ) |  |  | - |  |  | $ | (48,935 | ) |   | Other comprehensive income (loss) before reclassifications |  |  | 18,108 |  |  |  | (1,572 | ) |  |  | - |  |  |  | 16,536 |  |   | Amounts reclassified from accumulated other comprehensive loss to income |  |  | (12,415 | ) |  |  | - |  |  |  | - |  |  |  | (12,415 | ) |   | Balance June 30, 2018 |  | $ | 24,682 |  |  |  | (69,496 | ) |  |  | - |  |  | $ | (44,814 | ) |   | Cumulative effect adjustment for adoption for ASU 2018-02 (1) |  |  | 2,371 |  |  |  | - |  |  |  | - |  |  |  | 2,371 |  |   | Cumulative effect adjustment for adoption for ASU 2016-01 (1) |  |  | (27,053 | ) |  |  | - |  |  |  | - |  |  |  | (27,053 | ) |   | Other comprehensive income (loss) before reclassifications  (2) |  |  | - |  |  |  | (4,487 | ) |  |  | (9,537 | ) |  |  | (14,024 | ) |   | Balance June 30, 2019 |  | $ | - |  |  |  | (73,983 | ) |  |  | (9,537 | ) |  | $ | (83,521 | ) |  |