Leases (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
		Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Quantitative Lease Disclosures [Abstract]
Renewal option period		5 years	5 years
Assets [Abstract]
Operating lease right-of-use assets		$ 35,648	$ 35,648	$ 0
Liabilities [Abstract]
Sundry payables and accrued expenses		8,053	8,053
Noncurrent operating lease liabilities		28,613	28,613	$ 0
Present value of lease liabilities		$ 36,666	$ 36,666
Operating Leases [Abstract]
Weighted average remaining lease term		6 years 1 month 6 days	6 years 1 month 6 days
Weighted average discount rate		3.80%	3.80%
Lease Expense [Abstract]
Operating lease expense	[1]	$ 2,210	$ 4,434
Excluded expenses of non lease			1,100
Cash Paid for the amounts included in the measurement of lease liabilities [Abstract]
Operating cash flows from operating leases			4,239
Right-of-use assets obtained in exchange for new lease obligations [Abstract]
Operating leases			744
Minimum Lease Payments [Abstract]
2019		4,342	4,342
2020		7,689	7,689
2021		7,027	7,027
2022		5,818	5,818
2023		5,281	5,281
Thereafter		11,316	11,316
Total lease payments		41,473	41,473
Less: Interest		(4,807)	(4,807)
Present value of lease liabilities		$ 36,666	$ 36,666
Maximum [Member]
Quantitative Lease Disclosures [Abstract]
Remaining operating lease terms			10 years

[1] Excludes expenses of approximately $1.1 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.