Securities (Other Securities) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Investment [Line Items]
FHLB	$ 13.3	$ 14.3
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Investment [Line Items]
Percentage of mortgage-backed securities issued by government-sponsored enterprises	80.00%

Percentage of Heartland's Mortgage-backed Securities, Issued by US Government Sponsored Enterprises

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- Definition

Line items represent reporting 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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 12

-Sentence Column A

+ Details

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 325

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6478792&loc=d3e63345-112809

+ Details

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- Details

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