Organization and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2017	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Restricted Cash	$ 13,000,000			$ 9,000,000
Accounting Standards Update 2017-07 [Member] | Cost of Sales [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement, Effect of Adoption, Quantification	1,000,000
Accounting Standards Update 2017-07 [Member] | Selling, General and Administrative Expenses [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement, Effect of Adoption, Quantification	1,000,000
Accounting Standards Update 2016-18 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
New Accounting Pronouncement, Effect of Adoption, Quantification	$ 4,000,000
Accounting Standards Update 2016-01 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impact on retained earnings		$ 2,000,000
Accounting Standards Update 2014-09 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impact on retained earnings			$ 0