Tax cuts and job act of 2017 reclassification from AOCI to retained earnings, tax effect.

No definition available.

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- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e681-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

+ Details

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- Definition

Amount after tax, before reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84158357&loc=d3e1436-108581

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

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- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669619-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669625-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84158357&loc=d3e1436-108581

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- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=84158357&loc=d3e1436-108581

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Accumulated Other Comprehensive Loss (Components of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Accumulated other comprehensive income (loss), beginning balance			$ (37,278)
Net current-period other comprehensive income (loss)	$ 628	$ 179	7,772	$ (2,859)
Accumulated other comprehensive income (loss), ending balance	(29,506)		(29,506)		$ (37,278)
Postretirement Benefits [Member]
Accumulated other comprehensive income (loss), beginning balance			(16,454)	(14,074)	(14,074)
Other comprehensive income (loss) before reclassification					(1,365)
Amounts reclassified from accumulated other comprehensive income (loss)			420		671
Net current-period other comprehensive income (loss)			420		(694)
Tax cuts and Jobs Act, reclassification tax effect from accumulated other comprehensive loss to accumulated deficit					(1,686)
Accumulated other comprehensive income (loss), ending balance	(16,034)		(16,034)		(16,454)
Proportionate Share of Telesat Other Comprehensive Income (Loss) [Member]
Accumulated other comprehensive income (loss), beginning balance			(20,824)	238	238
Other comprehensive income (loss) before reclassification			7,352		(18,280)
Amounts reclassified from accumulated other comprehensive income (loss)
Net current-period other comprehensive income (loss)			7,352		(18,280)
Tax cuts and Jobs Act, reclassification tax effect from accumulated other comprehensive loss to accumulated deficit					(2,782)
Accumulated other comprehensive income (loss), ending balance	(13,472)		(13,472)		(20,824)
Accumulated Other Comprehensive Loss [Member]
Accumulated other comprehensive income (loss), beginning balance			(37,278)	$ (13,836)	(13,836)
Other comprehensive income (loss) before reclassification			7,352		(19,645)
Amounts reclassified from accumulated other comprehensive income (loss)			420		671
Net current-period other comprehensive income (loss)			7,772		(18,974)
Tax cuts and Jobs Act, reclassification tax effect from accumulated other comprehensive loss to accumulated deficit					(4,468)
Accumulated other comprehensive income (loss), ending balance	$ (29,506)		$ (29,506)		$ (37,278)