Long-Term Debt - Schedule of Long-Term Debt (Parenthetical) (Details)	9 Months Ended	12 Months Ended
Sep. 30, 2019	Dec. 31, 2018
Maximum
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.75%
Minimum
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.00%
4.200% Senior Notes, Semi-Annual Interest Payments, Net of the Unamortized Discount, Balloon Due 2024
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage	4.20%	4.20%
Debt instrument maturity year	2024	2024
4.500% Senior Notes, Semi-Annual Interest Payments, Net of the Unamortized Discount, Balloon Due 2029
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage	4.50%
Debt instrument maturity year	2029
5-year Term-Loan Facility Expires in 2022
Debt Instrument [Line Items]
Debt instrument maturity year	2022	2022
Line of credit facility, expiration period	5 years	5 years
Line of credit facility, expiration date	Jun. 28, 2022	Jun. 28, 2022
5-year Term-Loan Facility Expires in 2022 \| Maximum \| LIBOR
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.75%	1.75%
5-year Revolving-Loan Facility, Periodic Interest Payments, LIBOR Plus up to 1.500%, Plus Commitment Fees up to 0.250%, Expires June 28, 2022
Debt Instrument [Line Items]
Line of credit facility, expiration period		5 years
Line of credit facility, expiration date		Jun. 28, 2022
5-year Revolving-Loan Facility, Periodic Interest Payments, LIBOR Plus up to 1.500%, Plus Commitment Fees up to 0.250%, Expires June 28, 2022 \| Maximum
Debt Instrument [Line Items]
Commitment fee, percentage		0.25%
5-year Revolving-Loan Facility, Periodic Interest Payments, LIBOR Plus up to 1.500%, Plus Commitment Fees up to 0.250%, Expires June 28, 2022 \| Maximum \| LIBOR
Debt Instrument [Line Items]
Debt instrument, variable interest rate		1.50%
5-year Term-Loan Facility Expires in 2023
Debt Instrument [Line Items]
Debt instrument maturity year	2023	2023
Line of credit facility, expiration period	5 years	5 years
Line of credit facility, expiration date	Dec. 21, 2023	Dec. 21, 2023
5-year Term-Loan Facility Expires in 2023 \| Maximum \| LIBOR
Debt Instrument [Line Items]
Debt instrument, variable interest rate	1.75%	1.75%

Debt Instruments Maturity Year

No definition available.

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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.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ 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

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_
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Period Type:	duration

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	duration

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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