Long-Term Debt Amortization of Term Loans (Details) - 6 months ended Jun. 30, 2016 - Loans Payable [Member] £ in Thousands, AUD in Thousands, $ in Thousands	AUD	USD ($)	GBP (£)	USD ($)
United States dollar term loan [Member]
Prepayments of debt		$ 102,000
Long-term Debt, Gross				$ 1,670,000
Debt Instrument, Interest Rate, Stated Percentage	2.46%		2.46%	2.46%
Australian dollar term loan [Member]
Prepayments of debt	AUD 16,000	$ 11,800
Long-term Debt, Gross	AUD 273,627			$ 203,770
Debt Instrument, Interest Rate, Stated Percentage	3.89%		3.89%	3.89%
British pound term loan [Member]
Long-term Debt, Gross			£ 101,681	$ 134,911
Debt Instrument, Interest Rate, Stated Percentage	2.51%		2.51%	2.51%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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