Organization and Description of Business - Additional Information (Details) $ / shares in Units, $ in Millions	Sep. 10, 2019 USD ($) $ / shares shares
Accounting Policies [Abstract]
Sale of stock, number of shares issued in transaction (in shares)	1,575,342
Sale of stock, price per share (in USD per share) \| $ / shares	$ 73.00
Underwriters' option to purchase additional shares of common stock (in shares)	205,479
Proceeds from Issuance of Common Stock \| $	$ 107.3

Underwriters' Option To Purchase Additional Shares Of Common Stock

No definition available.

Name:	irtc_UnderwritersOptionToPurchaseAdditionalSharesOfCommonStock
Namespace Prefix:	irtc_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

+ Details

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

- Definition

The cash inflow from the additional capital contribution to the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfCommonStock
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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