Leases Operating Lease Costs (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Obligation with Joint and Several Liability Arrangement [Line Items]
Cash paid for amounts included in the measurement of operating lease liabilities	$ 2,197
Right-of-use assets obtained in exchange for lease liabilities	$ 37,863
Weighted-average remaining lease term-operating leases ( in years )	7 years 3 months 18 days
Weighted-average discount rate-operating leases ( as a percent )	5.41%
Selling, General and Administrative Expenses
Obligation with Joint and Several Liability Arrangement [Line Items]
Operating lease cost	$ 2,239
Short term and variable lease cost	460
Present value of lease liabilities	$ 2,699