Securities - Summary of Securities Available-for-Sale and Restricted Stock (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized Cost, Available-for-sale	$ 107,451	$ 111,874
Gross Unrealized Gains, Available-for-sale	1,439	701
Gross Unrealized (Losses), Available-for-sale	(627)	(429)
Available-for-sale, at fair value	108,263	112,146
Amortized Cost, Held to maturity	11,242	13,869
Gross Unrealized Gains, Held to maturity	300	143
Gross Unrealized (Losses), Held to maturity		(62)
Fair Value, Held to maturity	11,542	13,950
Amortized Cost	123,360	130,410
Gross Unrealized Gains	1,765	883
Gross Unrealized (Losses)	(627)	(491)
Fair Value	124,498	130,802
U.S. Treasury Security [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized Cost, Available-for-sale	999	998
Gross Unrealized Gains, Available-for-sale	21	1
Available-for-sale, at fair value	1,020	999
U.S. Government Agencies [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized Cost, Available-for-sale	2,000	5,500
Gross Unrealized Gains, Available-for-sale	3
Gross Unrealized (Losses), Available-for-sale		(4)
Available-for-sale, at fair value	2,003	5,496
Amortized Cost, Held to maturity	3,000	4,999
Gross Unrealized Gains, Held to maturity	8
Gross Unrealized (Losses), Held to maturity		(6)
Fair Value, Held to maturity	3,008	4,993
Mortgage-Backed Securities of Government Agencies [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized Cost, Available-for-sale	74,328	75,676
Gross Unrealized Gains, Available-for-sale	1,104	326
Gross Unrealized (Losses), Available-for-sale	(225)	(145)
Available-for-sale, at fair value	75,207	75,857
Amortized Cost, Held to maturity	8,242	8,870
Gross Unrealized Gains, Held to maturity	292	143
Gross Unrealized (Losses), Held to maturity		(56)
Fair Value, Held to maturity	8,534	8,957
Asset-Backed Securities of Government Agencies [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized Cost, Available-for-sale	910	934
Gross Unrealized (Losses), Available-for-sale	(105)	(17)
Available-for-sale, at fair value	805	917
State and Political Subdivisions [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized Cost, Available-for-sale	20,648	21,161
Gross Unrealized Gains, Available-for-sale	309	351
Gross Unrealized (Losses), Available-for-sale		(1)
Available-for-sale, at fair value	20,957	21,511
Corporate Bonds [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized Cost, Available-for-sale	8,566	7,605
Gross Unrealized Gains, Available-for-sale	2	23
Gross Unrealized (Losses), Available-for-sale	(297)	(262)
Available-for-sale, at fair value	8,271	7,366
Equity Securities [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized Cost, Equity securities	53	53
Gross Unrealized Gains, Equity securities	26	39
Fair Value, Equity securities	79	92
Restricted Stock [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortized Cost	4,614	4,614
Fair Value	$ 4,614	$ 4,614

Equity securities, FV-NI, cost with and without readily determinable value.

No definition available.

Name:	csbb_EquitySecuritiesFvNiCostWithAndWithoutReadilyDeterminableValue
Namespace Prefix:	csbb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Equity securities, FV-NI, unrealized gain with and without readily determinable value.

+ References

No definition available.

+ Details

Name:	csbb_EquitySecuritiesFvNiUnrealizedGainWithAndWithoutReadilyDeterminableValue
Namespace Prefix:	csbb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Marketable Securities Amortized Cost

+ References

No definition available.

+ Details

Name:	csbb_MarketableSecuritiesAmortizedCost
Namespace Prefix:	csbb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Marketable Securities Fair Value

+ References

No definition available.

+ Details

Name:	csbb_MarketableSecuritiesFairValue
Namespace Prefix:	csbb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Marketable Securities Unrealized Gain

+ References

No definition available.

+ Details

Name:	csbb_MarketableSecuritiesUnrealizedGain
Namespace Prefix:	csbb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Marketable Securities Unrealized Losses

+ References

No definition available.

+ Details

Name:	csbb_MarketableSecuritiesUnrealizedLosses
Namespace Prefix:	csbb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

+ Details

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

- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

+ Details

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

- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

+ Details

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

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

+ Details

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

- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI) and investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

+ Details

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

- Definition

Amount of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118954083&loc=d3e26610-111562

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

+ Details

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

- Definition

Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

+ Details

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

- Definition

Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

+ Details

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

- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27232-111563

+ Details

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

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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

- Details

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