Subsequent Events (Details) $ in Thousands	1 Months Ended
	Apr. 30, 2019 USD ($) extension	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Subsequent Event [Line Items]
Equity method investments		$ 48,734	$ 64,489
Zipnosis
Subsequent Event [Line Items]
Equity method investments			8,500
Syapse, Inc.
Subsequent Event [Line Items]
Equity method investments			15,600
meQuilibrium
Subsequent Event [Line Items]
Equity method investments			$ 11,500
Subsequent Event
Subsequent Event [Line Items]
Repayments of debt	$ 27,400
Repurchased face amount	24,000
Interest repaid	2,900
Accrued interest repaid	$ 500
Term of lease	18 months
Number of renewal terms | extension	3
Renewal term	6 months
Subsequent Event | Zipnosis
Subsequent Event [Line Items]
Payments to acquire equity method investments	$ 1,500
Subsequent Event | Syapse, Inc.
Subsequent Event [Line Items]
Payments to acquire equity method investments	3,000
Subsequent Event | meQuilibrium
Subsequent Event [Line Items]
Payments to acquire equity method investments	$ 1,500