Number of types of subsequent events.

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- Definition

Redemption price, percentage of principal amount

+ References

No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)(4)

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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-Publisher FASB

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

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-Paragraph 13

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Subsequent Events (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended	0 Months Ended
	Dec. 31, 2014 item	Feb. 23, 2015	Jan. 15, 2015
Subsequent Event [Line Items]
Number of types of subsequent events	2sf_NumberOfTypesOfSubsequentEvents
Stated interest rate	5.375%
Senior Notes 4.250% Due 2024 [Member]
Subsequent Event [Line Items]
Redemption price, percentage of principal amount	100.00%
Stated interest rate	4.25%
Subsequent Event [Member] \| Steme Agee Group, Inc. [Member]
Subsequent Event [Line Items]
Common stock consideration to be paid, price per share		$ 51.55
Value of merger consideration		$ 150.0
Subsequent Event [Member] \| Steme Agee Group, Inc. [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Shares expected to be issued		1.42
Expected cash consideration		77.0
Subsequent Event [Member] \| Steme Agee Group, Inc. [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Shares expected to be issued		1.62
Expected cash consideration		$ 66.0
Senior notes 6.70%, due 2022 [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Redemption price, percentage of principal amount			100.00%
Stated interest rate			6.70%