Number of loans resolved and/or charged-off during the period.

No definition available.

Name:	nbhc_FinancingReceivableRecordedInvestmentResolvedAndChargedOff
Namespace Prefix:	nbhc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The increase (decrease) in recorded Investment in financing receivables that are related to loans resolved and charged-off during the period.

+ References

No definition available.

+ Details

Name:	nbhc_FinancingReceivableRecordedInvestmentResolvedAndChargedOffDuringPeriod
Namespace Prefix:	nbhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The increase (decrease) in recorded Investment in financing receivables that are on non-accrual at the balance sheet date during the reporting period.

+ References

No definition available.

+ Details

Name:	nbhc_IncreaeDecreaseFinancingReceivableRecordedInvestmentPastDue
Namespace Prefix:	nbhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The percentage increase (decrease) in recorded Investment in financing receivables that are past due at the balance sheet date during the reporting period.

+ References

No definition available.

+ Details

Name:	nbhc_IncreaeDecreaseFinancingReceivableRecordedInvestmentPastDuePercent
Namespace Prefix:	nbhc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The increase (decrease) in recorded Investment in gross financing receivables during the reporting period.

+ References

No definition available.

+ Details

Name:	nbhc_IncreaeDecreaseNotesReceivableGross
Namespace Prefix:	nbhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Includes amounts for loans and leases covered and not covered under loss sharing agreements.

+ References

No definition available.

+ Details

Name:	nbhc_LoansAndLeasesReceivableDeferredDiscountFeesAndCosts
Namespace Prefix:	nbhc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Indicates the number of loan relationships.

+ References

No definition available.

+ Details

Name:	nbhc_NumberOfLoanRelationships
Namespace Prefix:	nbhc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of Commercial Substandard Loans.

+ References

No definition available.

+ Details

Name:	nbhc_NumberofCommercialSubstandardLoans
Namespace Prefix:	nbhc_
Data Type:	xbrli:integerItemType
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

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

+ 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=49124121&loc=d3e5111-111524

+ Details

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

- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953401-111524

+ Details

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

- Definition

Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(3))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CommercialLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=nbhc_NonAccrualMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=nbhc_EnergyLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=nbhc_OtherMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=nbhc_NonAccountingStandardCodificationThreeHundredTenToTenMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=nbhc_AccountingStandardCodificationThreeHundredTenToThirtyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementScenarioAxis=nbhc_LoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=nbhc_OwnerOccupiedCommercialMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=nbhc_NonOwnerOccupiedCommercialMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_SubstandardMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_UnlikelyToBeCollectedFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InternalCreditAssessmentAxis=us-gaap_SpecialMentionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Loans - Narrative Section (Details) $ in Thousands	6 Months Ended
Loans - Narrative Section (Details) $ in Thousands	Jun. 30, 2016 USD ($) loan	Dec. 31, 2015 USD ($)	Jun. 30, 2015 USD ($)
Debt Instrument [Line Items]
Fees and cost related to loans	$ 7,600	$ 8,100
Carrying amount of loan investments	2,738,504	2,587,673	$ 2,328,524
Commercial Loan [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	1,490,749	1,427,420
Non Accrual [Member]
Debt Instrument [Line Items]
Recorded investment, non-accrual status	37,400	25,600
Increase (decrease) in non-accrual loans	$ 11,800
Percentage increase (decrease) in past due loans	45.90%
Non Accrual [Member] \| Energy Loans [Member]
Debt Instrument [Line Items]
Number of loan relationships \| loan	2
Increase (decrease) in non-accrual loans	$ 20,100
Number of loans resolved and/or charged-off \| loan	1
Decrease related to loans resolved and/or charged-off	$ 6,200
Non Accrual [Member] \| Other
Debt Instrument [Line Items]
Increase (decrease) in non-accrual loans	(2,100)
Non ASC 310-30 [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	2,569,222	2,384,843
Non ASC 310-30 [Member] \| Commercial Loan [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	1,443,874	1,369,946
ASC 310-30 [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	169,282	202,830
ASC 310-30 [Member] \| Commercial Loan [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	46,875	57,474
Total Loans [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	2,738,504	2,587,673
Total Loans [Member] \| Non ASC 310-30 [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	2,569,222	2,384,843
Recorded investment, non-accrual status	37,428	25,647
Total past due loans	23,444	20,042
Total Loans [Member] \| Non ASC 310-30 [Member] \| Energy Loans [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	104,663	146,880
Recorded investment, non-accrual status	25,850	12,008
Total past due loans	12,222	5,804
Total Loans [Member] \| Non ASC 310-30 [Member] \| Commercial Loan [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	1,443,874	1,369,946
Recorded investment, non-accrual status	32,897	20,095
Total past due loans	18,069	10,611
Total Loans [Member] \| Non ASC 310-30 [Member] \| Owner-Occupied [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	191,668	184,619
Recorded investment, non-accrual status	906	1,273
Total past due loans	1,286	547
Total Loans [Member] \| Non ASC 310-30 [Member] \| Non Owner-Occupied [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	321,310	276,121
Recorded investment, non-accrual status	71	1,013
Total past due loans	747	3,490
Total Loans [Member] \| ASC 310-30 [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	169,282	202,830
Total Loans [Member] \| ASC 310-30 [Member] \| Commercial Loan [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	46,875	57,474
Total Loans [Member] \| Substandard [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	117,549	152,911
Total Loans [Member] \| Substandard [Member] \| Non ASC 310-30 [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	45,134	61,144
Total Loans [Member] \| Substandard [Member] \| Non ASC 310-30 [Member] \| Energy Loans [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	16,588	16,098
Total Loans [Member] \| Substandard [Member] \| Non ASC 310-30 [Member] \| Commercial Loan [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	33,471	48,451
Total Loans [Member] \| Substandard [Member] \| Non ASC 310-30 [Member] \| Owner-Occupied [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	4,837	4,916
Total Loans [Member] \| Substandard [Member] \| Non ASC 310-30 [Member] \| Non Owner-Occupied [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	4,683	5,722
Total Loans [Member] \| Substandard [Member] \| ASC 310-30 [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	72,415	91,767
Total Loans [Member] \| Substandard [Member] \| ASC 310-30 [Member] \| Commercial Loan [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	15,180	21,303
Total Loans [Member] \| Substandard and Doubtful \| Non ASC 310-30 [Member] \| Energy Loans [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	$ 29,300	18,200
Number of commercial substandard loans \| loan	2
Increase (decrease) in loan investments	$ 11,100
Total Loans [Member] \| Special Mention [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	70,185	69,888
Total Loans [Member] \| Special Mention [Member] \| Non ASC 310-30 [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	67,783	67,051
Total Loans [Member] \| Special Mention [Member] \| Non ASC 310-30 [Member] \| Energy Loans [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	15,746	36,503
Total Loans [Member] \| Special Mention [Member] \| Non ASC 310-30 [Member] \| Commercial Loan [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	$ 54,662	52,901
Number of commercial substandard loans \| loan	3
Increase (decrease) in loan investments	$ 15,900
Total Loans [Member] \| Special Mention [Member] \| Non ASC 310-30 [Member] \| Owner-Occupied [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	$ 14,531	5,595
Number of commercial substandard loans \| loan	1
Increase (decrease) in loan investments	$ (7,200)
Total Loans [Member] \| Special Mention [Member] \| Non ASC 310-30 [Member] \| Non Owner-Occupied [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	7,507	8,091
Total Loans [Member] \| Special Mention [Member] \| ASC 310-30 [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	2,402	2,837
Total Loans [Member] \| Special Mention [Member] \| ASC 310-30 [Member] \| Commercial Loan [Member]
Debt Instrument [Line Items]
Carrying amount of loan investments	$ 462	$ 787