Basis of Presentation and Summary of Significant Accounting Policies - Revenue Recognition, Related Sales Allowance and Accruals (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) deliverable	Jun. 30, 2016 USD ($)
Product Revenue
Gross product sales	$ 234,354	$ 176,581	$ 441,078	$ 328,773
Provision for product sales allowances and accruals:
Contractual adjustments	75,684	53,938	145,512	99,519
Governmental rebates	28,328	19,660	52,707	36,707
Total	104,012	73,598	198,219	136,226
Product sales, net	$ 130,342	$ 102,983	$ 242,859	$ 192,547
Service Revenue
Number of service revenue deliverables \| deliverable			2
Prepayment term for storage of newborn cord blood and tissue units (in years)			18 years

The aggregate selling price reductions recognized during an accounting period due to contractual adjustments.

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Number of deliverables

+ References

No definition available.

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- Definition

The prepayment term for storage of newborn cord blood and tissue units ("storage services").

+ References

No definition available.

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- Definition

Product Revenue [Abstract]

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No definition available.

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- Definition

The aggregate selling price reductions recognized during an accounting period due to government rebates.

+ References

No definition available.

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- Definition

n/a.

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No definition available.

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- Definition

Aggregate of: (i) sales discounts given by the entity, including, but not limited to, early payments of accounts due, (ii) the total deduction from sales during the period arising from goods returned by customers (other than under warranty provisions), and (iii) price reductions (allowance, price protection agreements) given by the entity. Discounts, returns and allowances are a deduction from gross revenue in arriving at net revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 50
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68069731&loc=d3e63676-111659

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1)(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 15
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=68051624&loc=d3e47468-111626

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- Definition

Aggregate revenue during the period from sale of goods in the normal course of business, before deducting returns, allowances and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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