Basis of Presentation and Significant Accounting Policies (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 27,997	$ 0
Operating lease liabilities	38,450
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	28,000
Operating lease liabilities	$ 38,500