Debt Instrument, Loan Period

No definition available.

Name:	sbac_DebtInstrumentLoanPeriod
Namespace Prefix:	sbac_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of face value price for issuance of term loan.

+ References

No definition available.

+ Details

Name:	sbac_PercentageOfFaceValuePriceForIssuanceOfTermLoan
Namespace Prefix:	sbac_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

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))
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+ Details

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

- 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
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+ Details

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

- Definition

The average effective interest rate during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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

- 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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

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

+ References

+ Details

Name:	us-gaap_DebtInstrumentPeriodicPayment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

+ Details

Name:	us-gaap_DeferredFinanceCostsGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Floor rate on an interest rate derivative such as an interest rate floor or collar. If market rates falls below the floor rate, a payment or receipt is triggered on the contract.

+ References

No definition available.

+ Details

Name:	us-gaap_DerivativeFloorInterestRate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Nominal or face amount used to calculate payments on the derivative liability.

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-Publisher FASB
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of cash outflow for the payment of debt classified as other, maturing after one year or the operating cycle, if longer.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
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Balance Type:	debit
Period Type:	duration

- Details

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Balance Type:
Period Type:

- Details

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Balance Type:
Period Type:

- Details

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- Details

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- Details

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- Details

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Debt (Term Loans under the Senior Credit Agreement) (Narrative) (Details) - USD ($)			3 Months Ended	12 Months Ended
	Feb. 01, 2019	Apr. 11, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Debt instrument, principal balance				$ 10,028,000,000	$ 9,405,000,000
Repayment of term loans				1,947,000,000	20,000,000	$ 20,000,000
2014 Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, face amount				$ 1,500,000,000
Debt instrument, maturity date				Mar. 24, 2021
Percentage of par value price for issuance of term loan				99.75%
Quarterly payments				$ 3,800,000
Debt instrument, principal balance					1,447,500,000
Financing fees				14,100,000
Repayment of term loans		$ 1,443,800,000	$ 3,800,000
Write-off of deferred financing fees		5,800,000
Discount related to debt		1,700,000
2015 Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, face amount				$ 500,000,000
Debt instrument, maturity date				Jun. 10, 2022
Percentage of par value price for issuance of term loan				99.00%
Quarterly payments				$ 1,300,000
Debt instrument, principal balance					$ 487,500,000
Financing fees				$ 5,500,000
Repayment of term loans		486,300,000	$ 1,300,000
Write-off of deferred financing fees		3,200,000
Discount related to debt		3,100,000
2018 Term Loan [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 2,400,000,000
Debt instrument, maturity date		Apr. 11, 2025		Apr. 11, 2025
Percentage of par value price for issuance of term loan		99.75%
Quarterly payments				$ 6,000,000
Accruing interest rate during the period				4.53%
Debt instrument, principal balance				$ 2,388,000,000
Financing fees		$ 16,800,000
Repayment of term loans				$ 12,000,000
2014 and 2015 Term Loans [Member]
Debt Instrument [Line Items]
Repayment of term loans		$ 1,930,000,000
Base Rate [Member] \| 2014 Term Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable interest rate				1.25%
Rate floor				0.00%
Base Rate [Member] \| 2015 Term Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable interest rate				1.25%
Rate floor				0.00%
Base Rate [Member] \| 2018 Term Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable interest rate		1.00%
Rate floor		0.00%
Eurodollar [Member] \| 2014 Term Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable interest rate				2.25%
Rate floor				0.00%
Eurodollar [Member] \| 2015 Term Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable interest rate				2.25%
Rate floor				0.00%
Eurodollar [Member] \| 2018 Term Loan [Member]
Debt Instrument [Line Items]
Basis spread on variable interest rate		2.00%
Rate floor		0.00%
Subsequent Event [Member] \| 2018 Term Loan [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Accruing interest rate during the period	4.495%
Loan period	4 years
Notional amount	$ 1,200,000,000
Subsequent Event [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| 2018 Term Loan [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Basis spread on variable interest rate	2.00%