Debt Schedule of Long-Term Debt Instruments (Tables)

12 Months Ended

Dec. 31, 2017

Debt Disclosure [Abstract]

Schedule of Maturities of Long-term Debt [Table Text Block]

The scheduled principal payments on long-term debt for each of the five years subsequent to December 31, 2017 is as follows (amounts in thousands):

Year	Principal payment amount
2018	$	286
2019	144,000
2020	—
2021	—
2022	—
Total	$	144,286