Loans and Leases (Financing receivables, non accrual status) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Receivables [Abstract]
Nonaccrual loans	$ 26,501htlf_NonaccrualLoans	$ 24,205htlf_NonaccrualLoans
Nonaccrual troubled debt restructured loans	522	865
Total nonaccrual loans	27,023	25,070
Accruing loans past due 90 days or more	9	0
Performing troubled debt restructured loans	$ 10,904	$ 12,133

Financing Receivable, Modifications, Recorded Investment, Nonaccrual Status

No definition available.

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- Definition

Financing Receivable, Modifications, Recorded Investment, Performing

+ References

No definition available.

+ Details

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- Definition

Nonaccrual Loans

+ References

No definition available.

+ Details

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- Definition

Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5111-111524

+ Details

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- Definition

Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

+ References

+ Details

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- Details

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