Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e31931-109318

Name:	us-gaap_DeferredIncomeTaxLiabilitiesNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

New accounting standards New accounting pronouncements (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclass from current assets - deferred income taxes to deferred credits and other liabilities	$ 652,413	$ 668,226	$ 662,326
Accounting Standards Update 2015-17 [Member] \| Restatement adjustment [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclass from current assets - deferred income taxes to deferred credits and other liabilities			$ 31,400