Summary of Significant Accounting Policies, Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Balance Sheet [Abstract]
Operating lease right-of-use assets	$ 36,020	$ 0
Sundry payables and accrued expenses	38,819	31,033
Noncurrent operating lease liabilities	$ 28,376	0
ASU 2016-02 [Member]
Balance Sheet [Abstract]
Operating lease right-of-use assets		38,580
Sundry payables and accrued expenses		38,265
Noncurrent operating lease liabilities		31,348
ASU 2016-02 [Member] | Adjustments due to Adoption of ASU 2016-02 [Member]
Balance Sheet [Abstract]
Operating lease right-of-use assets		38,580
Sundry payables and accrued expenses		7,232
Noncurrent operating lease liabilities		$ 31,348