Amount of the total principal payments made during the annual reporting period.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Amount of the required periodic payments applied to principal.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

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No definition available.

+ Details

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Date the credit facility first became available, in CCYY-MM-DD format.

+ References

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
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LONG-TERM DEBT (Details)					12 Months Ended
LONG-TERM DEBT (Details)	Aug. 31, 2016 EUR (€)	May 16, 2016 USD ($)	Aug. 26, 2015 GBP (£)	Jun. 11, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2016 CAD	Dec. 31, 2015 USD ($)	Dec. 31, 2015 CAD	Dec. 31, 2014 USD ($)	Dec. 31, 2016 EUR (€)	Sep. 30, 2014 CAD
Debt Instrument [Line Items]
Repayments debt					$ 262,248,000		$ 52,838,000		$ 170,907,000
August 2016 Credit Agreement [Member] \| Term loan [Member]
Debt Instrument [Line Items]
Face amount of debt \| €	€ 110,000,000
Debt issuance costs and discounts \| €	€ 500,000
Debt, term	5 years
Effective interest rate					0.45%					0.45%
August 2016 Credit Agreement [Member] \| Revolving credit facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity \| €	€ 20,000,000
Commitment fee percentage					0.1225%	0.1225%
Long-term line of credit, outstanding borrowings \| €										€ 5,000,000
Effective interest rate					0.35%					0.35%
Senior notes [Member] \| Unsecured Senior Notes, 3.75% [Member]
Debt Instrument [Line Items]
Face amount of debt		$ 400,000,000
Stated interest rate		3.75%			3.75%					3.75%
Basis points		0.20%
Debt issuance costs and discounts		$ 7,000,000
Debt, fair value					$ 371,000,000
Senior notes [Member] \| Unsecured Senior Notes, 3.75% [Member] \| Debt redemption, period one [Member]
Debt Instrument [Line Items]
Debt redemption percentage		101.00%
Senior notes [Member] \| Unsecured Senior Notes, 3.75% [Member] \| Debt redemption, period two [Member]
Debt Instrument [Line Items]
Debt redemption percentage		100.00%
Senior notes [Member] \| Unsecured Senior Notes, 4.60% [Member]
Debt Instrument [Line Items]
Face amount of debt				$ 1,000,000,000
Stated interest rate				4.60%	4.60%					4.60%
Basis points				0.25%
Debt issuance costs and discounts				$ 11,000,000
Debt, fair value					$ 1,100,000,000		$ 1,000,000,000
Senior notes [Member] \| Unsecured Senior Notes, 4.60% [Member] \| Debt redemption, period one [Member]
Debt Instrument [Line Items]
Debt redemption percentage				101.00%
Senior notes [Member] \| Unsecured Senior Notes, 4.60% [Member] \| Debt redemption, period two [Member]
Debt Instrument [Line Items]
Debt redemption percentage				100.00%
Line of credit [Member] \| Revolving credit facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity \| £			£ 20,000,000
Commitment fee percentage					0.26%	0.26%
Long-term line of credit, outstanding borrowings					$ 0
Term loan [Member] \| British pound term loan [Member]
Debt Instrument [Line Items]
Face amount of debt \| £			£ 160,000,000
Debt, term			5 years
Semi annual payments \| £			£ 4,000,000
Weighted average interest rate					1.17%		1.26%			1.17%
Revolving credit facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity \| CAD											CAD 175,000,000
Weighted average interest rate					1.59%					1.59%
Commitment fee percentage					0.07%	0.07%
Revolving credit facility, initiation date					Sep. 29, 2014	Sep. 29, 2014
Revolving credit facility, maturity date					Sep. 24, 2019	Sep. 24, 2019
Proceeds from revolving credit facility \| CAD						CAD 135,000,000		CAD 150,000,000
Required principal payments					$ 0
Euro term loan and revolving credit facility [Member]
Debt Instrument [Line Items]
Repayments debt \| €	€ 102,500,000
Euro Interbank Offered Rate (EURIBOR) [Member] \| August 2016 Credit Agreement [Member] \| Term loan [Member]
Debt Instrument [Line Items]
Basis points	0.45%
Euro Interbank Offered Rate (EURIBOR) [Member] \| August 2016 Credit Agreement [Member] \| Revolving credit facility [Member]
Debt Instrument [Line Items]
Basis points	0.35%