Other Financial Information (Summary of Changes in Operating Working Capital) (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Other Financial Information [Abstract]
Accounts receivable	$ (11,921)	$ (32,463)
Inventories	3,412	(36,386)
Prepaid expenses and other current assets	23,978	(11,859)
Accounts payable and accrued liabilities	17,955	67,207
Income taxes payable	24,003	(20,046)
Current deferred income tax liabilities	0	8,637
Net decrease (increase) in noncash operating working capital	$ 57,427	$ (24,910)

Other Financial Information [Abstract]

No definition available.

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- Definition

The increase (decrease) during the reporting period in the amounts payable to vendors for goods and services received and the amount of obligations and expenses incurred but not paid.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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- Definition

The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

+ References

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- Definition

The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

+ References

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- Definition

The increase (decrease) during the reporting period in the amounts payable to taxing authorities for taxes that are based on the reporting entity's earnings, net of amounts receivable from taxing authorities for refunds of overpayments or recoveries of income taxes.

+ References

No definition available.

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- Definition

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

+ References

+ Details

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- Definition

The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

+ References

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- Definition

The increase (decrease) during the reporting period in the value of prepaid expenses and other assets not separately disclosed in the statement of cash flows, for example, deferred expenses, intangible assets, or income taxes.

+ References

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