Summary of Significant Accounting Policies (New Accounting Pronouncements) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 16,388		$ 0
Long-term operating lease liabilities	16,973
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets		$ 18,400
Long-term operating lease liabilities	$ 18,400	$ 18,400