Revenues - Unearned Incentive Income Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue Recognition and Deferred Revenue [Abstract]
Effect of Adoption of ASU 2014-09 on Unearned Incentive			$ (99,422)
Beginning of Year	$ 61,397	$ 143,710	96,079
Amounts collected during the period	24,946	54,538	53,915
Amounts recognized during the period	(25,545)	(37,429)	(6,284)
End of Period	$ 60,798	$ 61,397	$ 143,710

Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

No definition available.

Name:	us-gaap_DeferredRevenueAdditions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration