Quarterly Results of Operations (Unaudited) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Transaction fees	$ 120,697,000	$ 121,905,000	$ 107,314,000	$ 98,692,000	$ 101,568,000	$ 100,813,000	$ 96,605,000	$ 124,508,000	$ 448,608,000		$ 423,494,000		$ 373,508,000
Investor fees (1)	24,313,000	20,499,000	21,116,000	21,180,000	26,027,000	18,477,000	14,656,000	20,487,000	87,108,000	[1]	79,647,000	[1]	43,787,000	[1]
Gain (Loss) on sales of loans (1)	10,353,000	6,680,000	4,445,000	1,892,000	115,000	(11,519,000)	(10,447,000)	4,699,000	23,370,000	[1]	(17,152,000)	[1]	4,885,000	[1]
Other revenue (1)	1,366,000	1,375,000	1,949,000	1,746,000	1,492,000	4,838,000	1,577,000	1,571,000	6,436,000	[1]	9,478,000	[1]	4,517,000	[1]
Interest income	141,471,000	151,532,000	157,260,000	160,996,000	167,230,000	171,868,000	179,685,000	177,879,000	611,259,000		696,662,000		552,972,000
Interest expense	(122,796,000)	(139,681,000)	(150,340,000)	(158,607,000)	(164,645,000)	(169,444,000)	(177,596,000)	(176,683,000)	(571,424,000)		(688,368,000)		(549,740,000)
Net fair value adjustments (1)	(18,949,000)	(8,280,000)	(2,171,000)	(1,417,000)	(1,265,000)	(477,000)	(1,040,000)	(167,000)	(30,817,000)	[1]	(2,949,000)	[1]	14,000	[1]
Net interest income and fair value adjustments (1)	(274,000)	3,571,000	4,749,000	972,000	1,320,000	1,947,000	1,049,000	1,029,000	9,018,000	[1]	5,345,000	[1]	3,246,000	[1]
Total net revenue	156,455,000	154,030,000	139,573,000	124,482,000	130,522,000	114,556,000	103,440,000	152,294,000	574,540,000		500,812,000		429,943,000
Sales and marketing	60,130,000	59,570,000	55,582,000	54,583,000	55,457,000	44,901,000	49,737,000	66,575,000	229,865,000		216,670,000		171,526,000
Origination and servicing	23,847,000	21,321,000	21,274,000	20,449,000	18,296,000	16,332,000	20,934,000	19,198,000	86,891,000		74,760,000		61,335,000
Engineering and product development	37,926,000	32,860,000	35,718,000	35,760,000	32,522,000	29,428,000	29,209,000	24,198,000	142,264,000		115,357,000		77,062,000
Other general and administrative	48,689,000	46,925,000	52,495,000	43,574,000	56,740,000	58,940,000	53,457,000	38,035,000	191,683,000		207,172,000		122,182,000
Class action litigation settlement	77,250,000	0	0	0					77,250,000		0		0
Goodwill impairment					0	1,650,000	35,400,000	0	0		37,050,000		0
Total operating expenses	247,842,000	160,676,000	165,069,000	154,366,000	163,015,000	151,251,000	188,737,000	148,006,000	727,953,000		651,009,000		432,105,000
Loss before income tax expense	(91,387,000)	(6,646,000)	(25,496,000)	(29,884,000)	(32,493,000)	(36,695,000)	(85,297,000)	4,288,000	(153,413,000)		(150,197,000)		(2,162,000)
Income tax expense (benefit)	711,000	13,000	(52,000)	(40,000)	(224,000)	(209,000)	(3,946,000)	151,000	632,000		(4,228,000)		2,833,000
Consolidated net loss	(92,098,000)	(6,659,000)	(25,444,000)	(29,844,000)	(32,269,000)	(36,486,000)	(81,351,000)	4,137,000	(154,045,000)		(145,969,000)		(4,995,000)
Less: Loss attributable to noncontrolling interests	(91,000)	(129,000)	10,000	0	0	0	0	0	(210,000)		0		0
LendingClub net loss	(92,007,000)	(6,530,000)	(25,454,000)	(29,844,000)	(32,269,000)	(36,486,000)	(81,351,000)	4,137,000	$ (153,835,000)		$ (145,969,000)		$ (4,995,000)
Other data:
Loan originations	$ 2,438,267,000	$ 2,442,867,000	$ 2,147,335,000	$ 1,958,749,000	$ 1,987,278,000	$ 1,972,034,000	$ 1,955,401,000	$ 2,750,033,000
Weighted-average common shares - Diluted (shares)	416,005,213	412,778,995	406,676,996	400,308,521	395,877,053	391,453,316	382,893,402	392,397,825	408,995,947		387,762,072		374,872,118
Weighted-average common shares - Basic (shares)	416,005,213	412,778,995	406,676,996	400,308,521	395,877,053	391,453,316	382,893,402	380,266,636	408,995,947		387,762,072		374,872,118
Net loss per share attributable to LendingClub:
Basic ($ per share)	$ (0.22)	$ (0.02)	$ (0.06)	$ (0.07)	$ (0.08)	$ (0.09)	$ (0.21)	$ 0.01	$ (0.38)		$ (0.38)		$ (0.01)
Diluted ($ per share)	$ (0.22)	$ (0.02)	$ (0.06)	$ (0.07)	$ (0.08)	$ (0.09)	$ (0.21)	$ 0.01	$ (0.38)		$ (0.38)		$ (0.01)

[1] Prior period amounts have been reclassified to conform to the current period presentation. See “Notes to Consolidated Financial Statements – Note 1. Basis of Presentation” for additional information.