Leases - Supplemental Cash flow Information to operating leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Supplemental cash flow information
Cash paid for amounts included in the measurement of operating lease liabilities	$ 8,479
Operating ROU assets obtained in exchange for lease liabilities	1,319
Supplemental balance sheet information
Operating lease right-of-use assets	40,049	$ 0
Operating lease liabilities:
Accrued expenses and other current liabilities	7,079
Operating lease liabilities	34,242	$ 0
Total operating lease liabilities	$ 41,321