Leases Leases (Details)	3 Months Ended
	Mar. 31, 2019 USD ($)
Operating Leased Assets [Line Items]
Rent expense related to operating lease liabilities	$ 700
Operating Lease, Right-of-Use Asset	12,100,000
Operating lease liabilities	16,800,000
Variable lease expense	400
Cash flows from operating leases	$ 800
Weighted average remaining lease term (years)	6 years
Weighted average discount rate - operating leases (1)	4.90%