Basis of Presentation - Accounting Standards (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Oct. 17, 2018	Jan. 01, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease liabilities	$ 5,178
Operating lease assets	4,983	$ 6,044
Deferred rent liability			$ 201
Current portion of lease liability	2,062	1,709
Long-term portion of lease liability	$ 3,116	4,536
Partners' Capital				$ 427,210		$ 433,647
Restatement Adjustment [Member] | Accounting Standards Update 2016-16 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Partners' Capital					$ 1,000
Other long-term liabilities					$ (1,000)
Restatement Adjustment [Member] | Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease liabilities		6,200
Operating lease assets		6,245
Deferred rent liability		(201)
Current portion of lease liability		1,709
Long-term portion of lease liability		$ 4,536