Authoritative Accounting Guidance (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use assets	$ 15,311
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Right-of-use assets	15,300
Lease liabilities	$ 16,700