Commitments and Contingencies Available Lines of Credit, Outstanding Standby Letter of Credits, and Bonds (Details) - USD ($) $ in Thousands		Sep. 30, 2016	Dec. 31, 2015	Jun. 23, 2015
Line of Credit Facility [Line Items]
Multicurrency revolving line of credit				$ 500,000
Line of Credit Facility, Capacity remaining to support letters of credit	[1]	$ 203,929	$ 253,426
Credit Facility [Member]
Line of Credit Facility [Line Items]
Multicurrency revolving line of credit	[2]	500,000	500,000
Long-term Line of Credit	[2]	132,597	151,837
Letters of Credit Outstanding, Amount	[2]	46,071	46,574
Unsecured Multicurrency Revolving Lines of Credit [Member]
Line of Credit Facility [Line Items]
Multicurrency revolving line of credit		98,655	97,989
Letters of Credit Outstanding, Amount		23,818	31,122
Short-term borrowings(2)	[3]	(2,205)	(3,884)
Line of Credit Facility, Remaining Borrowing Capacity		72,632	62,983
Surety Bond [Member]
Line of Credit Facility [Line Items]
Unsecured surety bonds in force		85,883	87,558
Line of Credit [Member]
Line of Credit Facility [Line Items]
Long-term Line of Credit		132,597	151,837
Line of Credit Facility, Remaining Borrowing Capacity	[2]	$ 321,332	$ 301,589

[1] During the nine months ended September 30, 2016, as a result of entering into the first and second amendments to the 2015 credit facility, the maximum limit available for additional standby LOCs under sub-facility was reduced from $300 million to $250 million.

[2] Refer to Note 6 for details regarding our secured credit facilities.

[3] Short-term borrowings are included in “Other current liabilities” on the Consolidated Balance Sheets.