Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss) attributable to BioTime, Inc.	$ (19,976,000)	$ 33,572,000	$ (46,991,000)
Net loss allocable to non-controlling interest	(3,313,000)	(14,951,000)	(11,143,000)
Adjustments to reconcile net income (loss) attributable to BioTime, Inc. to net cash used in operating activities:
BioTime’s share of losses and impairment of Ascendance		4,671,000	35,000
Gain on sale of assets	(1,754,000)
Depreciation expense, including amortization of leasehold improvements	947,000	1,180,000	1,078,000
Amortization of intangible assets	2,349,000	3,577,000	5,256,000
Stock-based compensation	3,932,000	7,951,000	11,050,000
Liability classified warrants	797,000
Subsidiary shareholder expense for subsidiary warrants		3,125,000
Subsidiary common stock issued in lieu of cash for services			486,000
Amortization of discount on related party convertible debt	640,000	448,000	245,000
Deferred income tax benefit			(4,516,000)
Foreign currency remeasurement and other (gain) loss	(1,761,000)	2,251,000	345,000
Loss on extinguishment of related party debt	2,799,000
Changes in operating assets and liabilities:
Accounts and grants receivable, net	(172,000)	187,000	(80,000)
Due from affiliates	1,157,000
Prepaid expenses and other current assets	145,000	(1,115,000)	(1,533,000)
Other long-term assets and liabilities	(22,000)	(56,000)	(120,000)
Accounts payable and accrued liabilities	1,299,000	12,000	1,673,000
Accrued interest on related party convertible debt			19,000
Deferred revenues and grant income	243,000	132,000	3,285,000
Deferred grant expense	(227,000)
Deferred rent liabilities	55,000	99,000	61,000
Net cash used in operating activities	(30,517,000)	(42,326,000)	(44,544,000)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of property and equipment	(1,326,000)	(2,248,000)	(1,241,000)
Payments on construction in progress		(278,000)	(4,093,000)
Purchase of foreign available-for-sale securities	(189,000)		(748,000)
Proceeds from sale of assets	200,000
Payment for Ascendance equity method investment			(500,000)
Security deposit paid and other	(12,000)	13,000	(859,000)
Net cash used in investing activities	(10,225,000)	(10,889,000)	(7,441,000)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common shares	48,875,000	20,125,000	35,470,000
Fees paid on sale of common shares	(3,798,000)	(1,515,000)
Proceeds from sale of subsidiary common shares and warrants	9,968,000	10,721,000	13,639,000
Fees paid on sale of subsidiary common shares and warrants		(879,000)	(693,000)
Proceeds from sale of common shares at-the-market, net of fees	835,000
Purchase and retirement of common shares from a related party	(843,000)
Proceeds from issuance of related party convertible debt	425,000	1,757,000	255,000
Reimbursement from landlord on construction in progress	198,000	567,000	3,789,000
Proceeds from exercise of subsidiary stock options	4,000	2,151,000	33,000
Proceeds from exercise of stock options	25,000		621,000
Proceeds from exercise of warrants			20,000
Common shares received and retired for employee taxes paid	(45,000)
Repayment of lease liability and capital lease obligation	(204,000)	(145,000)	(59,000)
Repayment of promissory notes	(49,000)
Proceeds from exercise of subsidiary warrants			11,700,000
Net cash provided by financing activities	55,391,000	32,782,000	64,775,000
Effect of exchange rate changes on cash and cash equivalents	101,000	292,000	(48,000)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	14,750,000	(20,141,000)	12,742,000
CASH AND CASH EQUIVALENTS:
At beginning of year	22,088,000	42,229,000	29,487,000
At end of year	36,838,000	22,088,000	42,229,000
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid during year for interest	156,000	94,000	119,000
SUPPLEMENTAL SCHEDULE OF NONCASH FINANCING AND INVESTING ACTIVITIES:
BioTime common stock issued to purchase Cell Cure ordinary shares and Convertible Notes from noncontrolling interests in Cell Cure	15,217,000
Extinguishment of related party convertible debt, including accrued interest, with BioTime common stock	2,680,000
Capital expenditure funded by capital lease liability	151,000	626,000	34,000
Construction in progress in accounts payable and accrued expenses			524,000
Landlord receivable			567,000
Lease liability		1,385,000	4,400,000
Conversion of preferred stock to common stock			3,500,000
Promissory notes in exchange of preferred share dividends			363,000
Common stock issued in lieu of cash for bonus and services		240,000
Equity method investment in Ascendance in exchange for assets			4,706,000
Asterias Biotherapeutics [Member]
Adjustments to reconcile net income (loss) attributable to BioTime, Inc. to net cash used in operating activities:
Gain on deconsolidation		(49,048,000)
Unrealized (gain) loss on equity method investment in at fair value	51,107,000	(34,361,000)
CASH FLOWS FROM INVESTING ACTIVITIES:
Deconsolidation of cash and cash equivalents		(8,376,000)
OncoCyte Corporation [Member]
Adjustments to reconcile net income (loss) attributable to BioTime, Inc. to net cash used in operating activities:
Gain on deconsolidation	(71,697,000)
Unrealized (gain) loss on equity method investment in at fair value	2,935,000
CASH FLOWS FROM INVESTING ACTIVITIES:
Deconsolidation of cash and cash equivalents	$ (8,898,000)