Derivative Instruments (Details) - Not designated as hedging instrument - Currency swap		1 Months Ended
Sep. 30, 2016 USD ($)	Feb. 28, 2011 CAD	Feb. 28, 2011 USD ($)
Derivative
Notional amount of derivative \| CAD		CAD 34,749,000
Periodic payment on derivative instrument \| CAD		CAD 589,000
Periodic receivable on derivative instrument			$ 593,000
Derivative instruments	$ 4,100,000
Gain (loss) on derivative instruments, net, pretax	$ 585,000

Derivative Instrument, Periodic Payment, Basis Amount

No definition available.

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- Definition

Derivative Instruments, Periodic Receivable, Basis Amount

+ References

No definition available.

+ Details

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Namespace Prefix:	crda_
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Period Type:	duration

- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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Balance Type:	na
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

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

+ Details

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- Definition

The cash inflow provided by derivative instruments during the period, which are classified as financing activities, excluding those designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3505-108585

+ Details

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- Details

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- Details

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