Additional Senior Notes Available for Request

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- Definition

Debt Instrument, Covenant, Consolidated Leverage Ratio In Period Of Acquisition, Maximum

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- Definition

Debt Instrument, Covenant, Consolidated Leverage Ratio, Maximum

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- Definition

Debt Instrument, Covenant, Fixed Charges Coverage Ratio, Minimum

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- Definition

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

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- Definition

Amount of assets pledged to secure a debt instrument.

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

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

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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.

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Amount of the required periodic payments including both interest and principal payments.

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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.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The effective interest rate during the reporting period.

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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.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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Long-Term Debt - Additional Information (Details)			3 Months Ended
Long-Term Debt - Additional Information (Details)	Jan. 04, 2019 USD ($)	Sep. 07, 2018 USD ($)	Mar. 31, 2019 GBP (£)	Mar. 31, 2019 USD ($)	Jan. 22, 2016 GBP (£)
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 600,000,000.0
Weighted average revolving interest rate, percentage			3.46%	3.46%
Line of credit facility, remaining borrowing capacity				$ 349,800,000
Debt instrument, collateral amount				600,000
Standby Letters of Credit
Debt Instrument [Line Items]
Proceeds from lines of credit				10,200,000
Senior Revolving Credit Facility Maturing in 2023 \| Standby Letters of Credit
Debt Instrument [Line Items]
Proceeds from lines of credit				2,700,000
Multi-currency Notes Due in 2031
Debt Instrument [Line Items]
Debt Instrument, Covenant, Consolidated Leverage Ratio In Period Of Acquisition, Maximum	4.00
Notes Payable \| Multi-currency Notes Due in 2031
Debt Instrument [Line Items]
Aggregate principal amount				71,500,000	£ 54,900,000.0
Annual installment debt payments			£ 6,100,000.0	7,900,000
Debt instrument, stated interest rate percentage					3.40%
Debt instrument, term		3 years
Additional senior notes available for request		$ 150,000,000
Senior notes payable				0
Minimum fixed charges coverage ratio (not less than)	1.50
Maximum consolidated leverage ratio (not to exceed)	3.50
Notes Payable \| Master Note Facility Due in 2022
Debt Instrument [Line Items]
Debt instrument, term	3 years
Additional senior notes available for request	$ 150,000,000
Senior notes payable				$ 0
Base Rate \| Senior Revolving Credit Facility Maturing in 2023
Debt Instrument [Line Items]
Interest rate margin, percentage		0.00%
Federal Funds Open Rate \| Senior Revolving Credit Facility Maturing in 2023
Debt Instrument [Line Items]
Interest rate margin, percentage		0.50%
Overnight Bank Funding Rate \| Senior Revolving Credit Facility Maturing in 2023
Debt Instrument [Line Items]
Interest rate margin, percentage		0.50%
London Interbank Offered Rate (LIBOR) \| Senior Revolving Credit Facility Maturing in 2023
Debt Instrument [Line Items]
Interest rate margin, percentage		1.00%
Minimum \| Senior Revolving Credit Facility Maturing in 2023
Debt Instrument [Line Items]
Interest rate margin, percentage		0.00%
Maximum \| Senior Revolving Credit Facility Maturing in 2023
Debt Instrument [Line Items]
Interest rate margin, percentage		175.00%