Loss Per Share - Narrative (Details) shares in Thousands	6 Months Ended
Jun. 30, 2020 $ / shares shares
5.00% / 7.00% Convertible Senior Secured PIK Toggle Notes Due August 31, 2022
Dilutive Earnings Per Share [Line Items]
Debt conversion price (in dollars per share)	$ 3.77
3.00% / 5.00% Convertible Senior Secured PIK Toggle Notes Due August 31, 2024
Dilutive Earnings Per Share [Line Items]
Debt conversion price (in dollars per share)	$ 0.46
Outstanding common stock equivalents (in shares) \| shares	212,400
Convertible Debt \| 5.00% / 7.00% Convertible Senior Secured PIK Toggle Notes Due August 31, 2022
Dilutive Earnings Per Share [Line Items]
Debt conversion price (in dollars per share)	$ 3.77
Convertible Debt \| 3.00% / 5.00% Convertible Senior Secured PIK Toggle Notes Due August 31, 2024
Dilutive Earnings Per Share [Line Items]
Debt conversion price (in dollars per share)	$ 0.46
Convertible Debt \| Minimum \| 5.00% / 7.00% Convertible Senior Secured PIK Toggle Notes Due August 31, 2022
Dilutive Earnings Per Share [Line Items]
Stated interest rate (as a percent)	5.00%
Convertible Debt \| Minimum \| 3.00% / 5.00% Convertible Senior Secured PIK Toggle Notes Due August 31, 2024
Dilutive Earnings Per Share [Line Items]
Stated interest rate (as a percent)	3.00%
Convertible Debt \| Maximum \| 5.00% / 7.00% Convertible Senior Secured PIK Toggle Notes Due August 31, 2022
Dilutive Earnings Per Share [Line Items]
Stated interest rate (as a percent)	7.00%
Convertible Debt \| Maximum \| 3.00% / 5.00% Convertible Senior Secured PIK Toggle Notes Due August 31, 2024
Dilutive Earnings Per Share [Line Items]
Stated interest rate (as a percent)	5.00%

[Line Items] for Dilutive Earnings Per Share [Table]

No definition available.

Name:	ctam_DilutiveEarningsPerShareLineItems
Namespace Prefix:	ctam_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The price per share of the conversion feature embedded in the debt instrument.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031898-161870

+ Details

Name:	us-gaap_DebtInstrumentConvertibleConversionPrice1
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 45
-Paragraph 40
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117326831&loc=d3e1930-109256

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

+ Details

Name:	us-gaap_IncrementalCommonSharesAttributableToConversionOfDebtSecurities
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=ctam_ConvertibleNotes5.007.00dueAugust312022Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=ctam_ConvertibleNotes300500DueAugust312024Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_ConvertibleDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: