Leases - Cumulative Effect of Adoption of New Leasing Standard (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
ASSETS
Property, plant and equipment - net			$ 1,032
Property, plant and equipment – net	$ 1,320	$ 1,032
Operating lease right-of-use assets	115,284	117,921	0
Total assets	1,162,886	1,152,547	1,034,626
Current liabilities:
Accounts Payable		318	318
Operating lease liabilities – short-term	26,022	24,794	0
Total current liabilities	253,727	309,518	284,724
Operating lease liabilities – long-term	89,503	93,127	0
Other liabilities		762	762
Total liabilities	742,323	732,209	614,288
Total equity		420,338	420,338
Total liabilities and equity	$ 1,162,886	1,152,547	$ 1,034,626
Accounting Standards Update 2016-02
ASSETS
Property, plant and equipment – net		0
Operating lease right-of-use assets		117,921
Total assets		117,921
Current liabilities:
Accounts Payable		0
Operating lease liabilities – short-term		24,794
Total current liabilities		24,794
Operating lease liabilities – long-term		93,127
Other liabilities		0
Total liabilities		117,921
Total equity		0
Total liabilities and equity		$ 117,921