Dividends (Details Narrative) (USD $)	3 Months Ended
Jun. 30, 2012	Jun. 14, 2011	Dec. 14, 2010 Pre-Stock Dividend Dated 04/20/2011
Quarterly dividend before increase			$ 0.15
Quarterly dividend after increase		$ 0.115	$ 0.1725
Dividends declared	$ 0.12
Date dividend increased declared	Feb. 10, 2012
Date dividend paid	Jul. 16, 2012

Quarterly dividend after declaration by Board of Directors of an increase in dividend rate.

No definition available.

Name:	CNIG_QuarterlyDividendAfterIncrease
Namespace Prefix:	CNIG_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Quarterly dividend before declaration by Board of Directors of an increase in dividend rate.

+ References

No definition available.

+ Details

Name:	CNIG_QuarterlyDividendBeforeIncrease
Namespace Prefix:	CNIG_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_DividendPayableDateToBePaidDayMonthAndYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The per share amount of a dividend declared, but not paid, as of the financial reporting date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 32

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_DividendsPayableAmountPerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_DividendsPayableDateDeclaredDayMonthAndYear
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration