Leases (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
		Sep. 30, 2019	Sep. 30, 2019	Dec. 31, 2018
Quantitative Lease Disclosures [Abstract]
Renewal option period		5 years	5 years
Assets [Abstract]
Operating lease right-of-use assets		$ 34,055	$ 34,055	$ 0
Liabilities [Abstract]
Sundry payables and accrued expenses		7,899	7,899
Noncurrent operating lease liabilities		27,214	27,214	$ 0
Present value of lease liabilities		$ 35,113	$ 35,113
Operating Leases [Abstract]
Weighted average remaining lease term		6 years	6 years
Weighted average discount rate		3.80%	3.80%
Lease Expense [Abstract]
Operating lease expense	[1]	$ 2,199	$ 6,633
Excluded expenses of non lease			1,900
Cash Paid for the amounts included in the measurement of lease liabilities [Abstract]
Operating cash flows from operating leases			6,490
Right-of-use assets obtained in exchange for new lease obligations [Abstract]
Operating leases			856
Minimum Lease Payments [Abstract]
2019		2,158	2,158
2020		7,787	7,787
2021		7,088	7,088
2022		5,861	5,861
2023		5,279	5,279
Thereafter		11,316	11,316
Total lease payments		39,489	39,489
Less: Interest		(4,376)	(4,376)
Present value of lease liabilities		$ 35,113	$ 35,113
Maximum [Member]
Quantitative Lease Disclosures [Abstract]
Remaining operating lease terms			10 years

[1] Excludes expenses of approximately $1.9 million related to non-lease components such as maintenance, property taxes, etc., and operating lease expense for leases with an initial term of 12 months or less, which is not material.