Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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Amount of asset related to consideration paid in advance for rent that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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Leases - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating Leased Assets [Line Items]
Operating lease assets	$ 17,082		$ 0
Operating lease liabilities	$ 17,862		$ 0
Accounting Standards Update 2016-02
Operating Leased Assets [Line Items]
Operating lease assets		$ 12,500
Prepaid rent		800
Operating lease liabilities		$ 13,300