Parent Company Only Financial Statements - Income Statement (Details) - USD ($)		12 Months Ended
	Oct. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Condensed Income Statements, Captions [Line Items]
Interest income		$ 227,980,000	$ 162,643,000	$ 103,472,000
Interest expense		87,898,000	54,600,000	25,438,000
Net interest income		140,082,000	108,043,000	78,034,000
Other noninterest income		7,973,000	5,394,000	4,141,000
Total noninterest income		67,880,000	103,765,000	172,921,000
Noninterest expense
Salaries and employee benefits		90,634,000	77,411,000	74,669,000
Professional services expense		6,859,000	4,878,000	4,937,000
Renewable energy tax credit investment impairment		602,000		690,000
Impairment expense on goodwill and other intangibles, net	$ 3,600,000	0	2,680,000	3,648,000
Other expense		7,545,000	9,652,000	12,017,000
Total noninterest expense		164,924,000	152,704,000	143,165,000
Net loss before equity in undistributed income of subsidiaries		23,465,000	46,046,000	98,254,000
Income tax benefit		5,431,000	(5,402,000)	(2,245,000)
Net income		18,034,000	51,448,000	100,499,000
Live Oak Bancshares, Inc.
Condensed Income Statements, Captions [Line Items]
Interest income		236,000	46,000	5,000
Interest expense			129,000	1,210,000
Net interest income		236,000	(83,000)	(1,205,000)
Other noninterest income		140,000	562,000	2,114,000
Total noninterest income		140,000	562,000	2,114,000
Noninterest expense
Salaries and employee benefits		12,408,000	10,117,000	10,531,000
Professional services expense		825,000	853,000	1,192,000
Renewable energy tax credit investment impairment		602,000		690,000
Impairment expense on goodwill and other intangibles, net			2,680,000	(4,350,000)
Other expense		999,000	1,844,000	2,588,000
Total noninterest expense		14,834,000	15,494,000	10,651,000
Net loss before equity in undistributed income of subsidiaries		(14,458,000)	(15,015,000)	(9,742,000)
Income tax benefit		(27,000)	(3,658,000)	(320,000)
Net loss		(14,431,000)	(11,357,000)	(9,422,000)
Equity in undistributed income of subsidiaries in excess of dividends from subsidiaries		32,465,000	62,805,000	109,921,000
Net income		$ 18,034,000	$ 51,448,000	$ 100,499,000