Leases - Leases Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Leases [Abstract]
Other assets	$ 136,210	$ 133,864
Current operating lease liability	21,808	23,137
Other noncurrent liabilities	116,249	114,686
Total operating lease liabilities	138,057	137,823
Net property, plant and equipment	58,972	59,494
Current portion of long-term debt	592	636
Long-term debt	58,620	58,888
Total finance lease liabilities	$ 59,212	$ 59,524
Weighted average remaining lease term, operating leases	15 years 10 months 24 days	11 years 4 months 24 days
Weighted average remaining lease term, finance leases	28 years	28 years 3 months 18 days
Weighted average discount rate, operating leases, percent	4.08%	3.84%
Weighted average discount rate, finance leases, percent	4.57%	4.56%