Condensed Consolidated Statements of Income (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Cost of sales, related party transactions	$ 0	$ 9,180	$ 0	$ 18,425

Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

No definition available.

Name:	us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration