Revenues and Business Information (Tables)

6 Months Ended

Jun. 30, 2019

Segment Reporting [Abstract]

Schedule of Geographical Distribution of Revenues and Assets

	Three Months Ended June 30,				Six Months Ended June 30,
	2019		2018		2019		2018
Revenues:
United States	$	132,246	$	193,557	$	254,926	$	372,239
Europe		16,005		13,896		22,721		37,332
Rest of World		5,272		12,952		13,659		30,252
Total	$	153,523	$	220,405	$	291,306	$	439,823

	June 30,		December 31,
	2019		2018
Assets:
United States	$	591,860	$	756,053
Europe		34,376		55,064
Rest of World		88,533		103,258
Total	$	714,769	$	914,375