Adoption of ASC Topic 842, Leases, Effective January 1, 2019 - Impacts of Adoption of Standard Related to Leases (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment	$ 305,097		$ 280,658
Prepaid expenses	11,477		10,294
Accrued and other liabilities	$ 104,443		97,724
ASC Topic 842 Leases [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment		$ 298,120
Prepaid expenses		10,258
Accrued and other liabilities		115,150
ASC Topic 842 Leases [Member] | Previously Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment			280,658
Prepaid expenses			10,294
Accrued and other liabilities			$ 97,724
ASC Topic 842 Leases [Member] | As Adjusted [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Property, plant and equipment		17,462
Prepaid expenses		(36)
Accrued and other liabilities		$ 17,426