Income Taxes - Reorganization Transactions - (Details) - USD ($) $ in Thousands		12 Months Ended
	Apr. 01, 2016	Dec. 31, 2017	Dec. 31, 2015
Income taxes
Current tax receivables related to transactions prior to Reorganization Transactions		$ 93,900
Unrecognized tax benefits		116,500
Indemnification receivable		22,600
Total state and local distribution taxes reported		92,100
Capital Distributions		2,118	$ 164,228
Net adjustments to pre-Reorganization indemnification receivables or payables and unrecognized tax benefits		$ 3,900
Reorganization Transactions on April 1, 2016
Income taxes
Current tax receivables recorded	$ 72,800
Unrecognized tax benefits	116,600
Indemnification payable	28,600
Certain tax related liabilities incurred	95,400
Expected federal tax benefit on distribution taxes	$ 33,400