Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
New Accounting Pronouncements [Abstract]
Renewal option period	5 years
Balance Sheet [Abstract]
Operating lease right-of-use asset	$ 35,648	$ 0
Sundry payables and accrued expenses		31,033
Noncurrent operating lease liabilities	$ 28,613	0
ASU 2016-02 [Member]
Balance Sheet [Abstract]
Operating lease right-of-use asset		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 asset		38,580
Sundry payables and accrued expenses		7,232
Noncurrent operating lease liabilities		$ 31,348