Contracts with Customers (Notes)	9 Months Ended
Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Long-term Contracts or Programs Disclosure [Text Block]	Contracts with Customers Unbilled receivables increased from $8,194 at December 31, 2017 to $9,936 at September 30, 2018, primarily driven by revenue recognized at BDS and BCA in excess of billings. Advances and progress billings increased from $48,042 at December 31, 2017 to $51,496 at September 30, 2018, primarily driven by advances on orders received in excess of revenue recognized at BCA. In the nine and three months ended September 30, 2018, we recognized revenue of $19,006 and $6,249 related to our Advances and progress billings at January 1, 2018. In the nine and three months ended September 30, 2017, we recognized revenue of $17,696 and $6,009 related to our Advances and progress billings at January 1, 2017.

The entire disclosure for long-term contracts or programs.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 912
-URI http://asc.fasb.org/topic&trid=2145070

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-URI http://asc.fasb.org/topic&trid=2122208

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 35
-URI http://asc.fasb.org/subtopic&trid=2197326

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