Leasing Arrangements - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 1,179
Operating cash flows from finance leases	5
Financing cash flows from finance leases	335	$ 3
Right-of-use assets, net obtained in exchange for new lease obligations:
Operating lease liabilities	22,523
Finance lease liabilities	$ 441