Summary of Significant Accounting Policies (Details) - USD ($)	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 65,373,000	$ 66,400,000	$ 0
Operating lease liabilities	$ 68,256
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets		66,400,000
Operating lease liabilities		$ 69,000,000.0