Financial Highlights - Per Share Operating Performance (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
ProShares VIX Short-Term Futures ETF [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 66.21	$ 104.6604	$ 142.6934
Net investment income (loss)	(0.2754)	(0.6622)	(1.0237)
Net realized and unrealized gain (loss)	(44.7209)	(37.7873)	(37.0093)
Change in net asset value from operations	(44.9963)	(38.4495)	(38.0330)
Net asset value, ending balance	21.21	66.21	104.6604
Market value per share, beginning balance	66.65	104.95	142.65
Market value per share, ending balance	$ 21.26	$ 66.65	$ 104.95
Total Return, at net asset value	(68.00%)	(36.70%)	(26.70%)
Total Return, at market value	(68.10%)	(36.50%)	(26.40%)
Ratios to Average Net Assets
Expense ratio	0.99%	0.95%	0.92%
Expense ratio, excluding brokerage commissions	0.85%	0.85%	0.85%
Net investment income (loss)	(0.75%)	(0.92%)	(0.88%)
ProShares VIX Mid-Term Futures ETF [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 53.96	$ 63.6020	$ 77.1837
Net investment income (loss)	(0.3333)	(0.5053)	(0.5666)
Net realized and unrealized gain (loss)	(11.4932)	(9.1341)	(13.0151)
Change in net asset value from operations	(11.8265)	(9.6394)	(13.5817)
Net asset value, ending balance	42.14	53.96	63.6020
Market value per share, beginning balance	53.99	63.89	77.16
Market value per share, ending balance	$ 42.34	$ 53.99	$ 63.89
Total Return, at net asset value	(21.90%)	(15.20%)	(17.60%)
Total Return, at market value	(21.60%)	(15.50%)	(17.20%)
Ratios to Average Net Assets
Expense ratio	0.93%	0.91%	0.87%
Expense ratio, excluding brokerage commissions	0.85%	0.85%	0.85%
Net investment income (loss)	(0.68%)	(0.88%)	(0.84%)
ProShares Short VIX Short-Term Futures ETF [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 50.81	$ 61.4004	$ 67.4993
Net investment income (loss)	(0.6090)	(0.8162)	(1.0247)
Net realized and unrealized gain (loss)	41.0242	(9.7692)	(5.0742)
Change in net asset value from operations	40.4152	(10.5854)	(6.0989)
Net asset value, ending balance	91.23	50.81	61.4004
Market value per share, beginning balance	50.45	61.16	67.47
Market value per share, ending balance	$ 90.98	$ 50.45	$ 61.16
Total Return, at net asset value	79.50%	(17.20%)	(9.00%)
Total Return, at market value	80.30%	(17.50%)	(9.40%)
Ratios to Average Net Assets
Expense ratio	1.39%	1.40%	1.49%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(1.15%)	(1.36%)	(1.46%)
ProShares Ultra VIX Short-Term Futures ETF [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 702.10	$ 3,136.4730	$ 8,385.5437
Net investment income (loss)	(1.9193)	(18.0602)	(72.6365)
Net realized and unrealized gain (loss)	(656.7016)	(2,416.3103)	(5,176.4342)
Change in net asset value from operations	(658.6209)	(2,434.3705)	(5,249.0707)
Net asset value, ending balance	43.48	702.10	3,136.4730
Market value per share, beginning balance	708.75	3,143.75	8,390.00
Market value per share, ending balance	$ 43.75	$ 708.75	$ 3,143.75
Total Return, at net asset value	(93.80%)	(77.60%)	(62.60%)
Total Return, at market value	(93.80%)	(77.50%)	(62.50%)
Ratios to Average Net Assets
Expense ratio	1.57%	1.65%	1.80%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(1.32%)	(1.61%)	(1.78%)
ProShares UltraShort Bloomberg Crude Oil [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 66.60	$ 38.9895	$ 15.8651
Net investment income (loss)	(0.3600)	(0.3924)	(0.1387)
Net realized and unrealized gain (loss)	(34.5434)	28.0038	23.2631
Change in net asset value from operations	(34.9034)	27.6114	23.1244
Net asset value, ending balance	31.70	66.60	38.9895
Market value per share, beginning balance	66.82	38.26	15.79
Market value per share, ending balance	$ 31.65	$ 66.82	$ 38.26
Total Return, at net asset value	(52.40%)	70.80%	145.80%
Total Return, at market value	(52.60%)	74.60%	142.30%
Ratios to Average Net Assets
Expense ratio	1.03%	1.07%	0.98%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.76%)	(1.04%)	(0.94%)
ProShares UltraShort Bloomberg Natural Gas [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 46.53	$ 27.9859	$ 23.3212
Net investment income (loss)	(0.6812)	(0.4438)	(0.1654)
Net realized and unrealized gain (loss)	(22.7492)	18.9893	4.8301
Change in net asset value from operations	(23.4304)	18.5455	4.6647
Net asset value, ending balance	23.10	46.53	27.9859
Market value per share, beginning balance	46.55	27.34	23.12
Market value per share, ending balance	$ 23.05	$ 46.55	$ 27.34
Total Return, at net asset value	(50.40%)	66.30%	20.00%
Total Return, at market value	(50.50%)	70.30%	18.30%
Ratios to Average Net Assets
Expense ratio	1.65%	1.55%	1.18%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(1.43%)	(1.50%)	(1.14%)
ProShares UltraShort Gold [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 115.88	$ 96.6516	$ 103.5180
Net investment income (loss)	(0.5542)	(0.9149)	(0.8233)
Net realized and unrealized gain (loss)	(23.9976)	20.1432	(6.0431)
Change in net asset value from operations	(24.5518)	19.2283	(6.8664)
Net asset value, ending balance	91.33	115.88	96.6516
Market value per share, beginning balance	115.83	100.22	103.53
Market value per share, ending balance	$ 90.54	$ 115.83	$ 100.22
Total Return, at net asset value	(21.20%)	19.90%	(6.60%)
Total Return, at market value	(21.80%)	15.60%	(3.20%)
Ratios to Average Net Assets
Expense ratio	0.95%	0.95%	0.95%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.70%)	(0.91%)	(0.91%)
ProShares UltraShort Silver [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 64.58	$ 57.8071	$ 44.8910
Net investment income (loss)	(0.2641)	(0.4968)	(0.3937)
Net realized and unrealized gain (loss)	(27.0070)	7.2680	13.3098
Change in net asset value from operations	(27.2711)	6.7712	12.9161
Net asset value, ending balance	37.31	64.58	57.8071
Market value per share, beginning balance	64.55	59.70	45.10
Market value per share, ending balance	$ 38.76	$ 64.55	$ 59.70
Total Return, at net asset value	(42.20%)	11.70%	28.80%
Total Return, at market value	(40.00%)	8.10%	32.40%
Ratios to Average Net Assets
Expense ratio	0.95%	0.95%	0.95%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.70%)	(0.91%)	(0.90%)
ProShares Short Euro [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 43.78	$ 40.0617	$ 35.5867
Net investment income (loss)	(0.3268)	(0.4096)	(0.3428)
Net realized and unrealized gain (loss)	1.6075	4.1246	4.8178
Change in net asset value from operations	1.2807	3.7150	4.4750
Net asset value, ending balance	45.06	43.78	40.0617
Market value per share, beginning balance	43.74	40.03	35.66
Market value per share, ending balance	$ 45.12	$ 43.74	$ 40.03
Total Return, at net asset value	2.90%	9.30%	12.60%
Total Return, at market value	3.20%	9.30%	12.30%
Ratios to Average Net Assets
Expense ratio	0.97%	0.97%	0.96%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.76%)	(0.95%)	(0.93%)
ProShares UltraShort Australian Dollar [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 58.46	$ 51.3790	$ 46.6384
Net investment income (loss)	(0.4268)	(0.5741)	(0.4272)
Net realized and unrealized gain (loss)	(2.6532)	7.6533	5.1678
Change in net asset value from operations	(3.0800)	7.0792	4.7406
Net asset value, ending balance	55.38	58.46	51.3790
Market value per share, beginning balance	58.15	51.37	46.66
Market value per share, ending balance	$ 55.24	$ 58.15	$ 51.37
Total Return, at net asset value	(5.30%)	13.80%	10.20%
Total Return, at market value	(5.00%)	13.20%	10.10%
Ratios to Average Net Assets
Expense ratio	1.03%	1.03%	1.01%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.79%)	(1.00%)	(0.97%)
ProShares UltraShort Euro [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 25.54	$ 21.5946	$ 17.0613
Net investment income (loss)	(0.1703)	(0.2256)	(0.1642)
Net realized and unrealized gain (loss)	1.7144	4.1716	4.6975
Change in net asset value from operations	1.5441	3.9460	4.5333
Net asset value, ending balance	27.08	25.54	21.5946
Market value per share, beginning balance	25.53	21.61	17.06
Market value per share, ending balance	$ 27.08	$ 25.53	$ 21.61
Total Return, at net asset value	6.00%	18.30%	26.60%
Total Return, at market value	6.10%	18.10%	26.70%
Ratios to Average Net Assets
Expense ratio	0.95%	0.95%	0.95%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.70%)	(0.90%)	(0.90%)
ProShares UltraShort Yen [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 87.94	$ 89.3336	$ 70.8640
Net investment income (loss)	(0.4974)	(0.8243)	(0.6412)
Net realized and unrealized gain (loss)	(7.1984)	(0.5704)	19.1108
Change in net asset value from operations	(7.6958)	(1.3947)	18.4696
Net asset value, ending balance	80.24	87.94	89.3336
Market value per share, beginning balance	87.89	89.30	70.91
Market value per share, ending balance	$ 80.25	$ 87.89	$ 89.30
Total Return, at net asset value	(8.80%)	(1.60%)	26.10%
Total Return, at market value	(8.70%)	(1.60%)	25.90%
Ratios to Average Net Assets
Expense ratio	0.95%	0.95%	0.95%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.71%)	(0.92%)	(0.90%)
ProShares Ultra Bloomberg Crude Oil [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 25.15	$ 101.4800	$ 320.8990
Net investment income (loss)	(0.1534)	(0.5621)	(2.1856)
Net realized and unrealized gain (loss)	(1.6662)	(75.7631)	(217.2334)
Change in net asset value from operations	(1.8196)	(76.3252)	(219.4190)
Net asset value, ending balance	23.34	25.15	101.4800
Market value per share, beginning balance	25.08	103.70	322.20
Market value per share, ending balance	$ 23.36	$ 25.08	$ 103.70
Total Return, at net asset value	(7.20%)	(75.20%)	(68.40%)
Total Return, at market value	(6.90%)	(75.80%)	(67.80%)
Ratios to Average Net Assets
Expense ratio	1.01%	1.02%	0.99%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.76%)	(0.98%)	(0.95%)
ProShares Ultra Bloomberg Natural Gas [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 18.57	$ 61.6491	$ 155.3534
Net investment income (loss)	(0.1579)	(0.4982)	(1.5167)
Net realized and unrealized gain (loss)	0.4364	(42.5811)	(92.1876)
Change in net asset value from operations	0.2785	(43.0793)	(93.7043)
Net asset value, ending balance	18.85	18.57	61.6491
Market value per share, beginning balance	18.48	63.12	157.12
Market value per share, ending balance	$ 18.96	$ 18.48	$ 63.12
Total Return, at net asset value	1.50%	(69.90%)	(60.30%)
Total Return, at market value	2.60%	(70.70%)	(59.80%)
Ratios to Average Net Assets
Expense ratio	1.34%	1.29%	1.13%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(1.12%)	(1.26%)	(1.10%)
ProShares Ultra Gold [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 29.73	$ 40.0011	$ 41.2553
Net investment income (loss)	(0.2751)	(0.3292)	(0.4078)
Net realized and unrealized gain (loss)	3.4482	(9.9424)	(0.8464)
Change in net asset value from operations	3.1731	(10.2716)	(1.2542)
Net asset value, ending balance	32.90	29.73	40.0011
Market value per share, beginning balance	29.73	38.41	41.26
Market value per share, ending balance	$ 33.20	$ 29.73	$ 38.41
Total Return, at net asset value	10.70%	(25.70%)	(3.00%)
Total Return, at market value	11.70%	(22.60%)	(6.90%)
Ratios to Average Net Assets
Expense ratio	0.95%	0.95%	0.95%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.69%)	(0.90%)	(0.91%)
ProShares Ultra Silver [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 27.06	$ 39.3657	$ 63.3305
Net investment income (loss)	(0.2717)	(0.3258)	(0.5348)
Net realized and unrealized gain (loss)	6.6499	(11.9761)	(23.4300)
Change in net asset value from operations	6.3782	(12.3019)	(23.9648)
Net asset value, ending balance	33.44	27.06	39.3657
Market value per share, beginning balance	27.08	38.05	63.04
Market value per share, ending balance	$ 32.09	$ 27.08	$ 38.05
Total Return, at net asset value	23.60%	(31.30%)	(37.80%)
Total Return, at market value	18.50%	(28.80%)	(39.60%)
Ratios to Average Net Assets
Expense ratio	0.95%	0.95%	0.95%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.69%)	(0.89%)	(0.91%)
ProShares Ultra Euro [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 15.51	$ 19.8744	$ 26.0346
Net investment income (loss)	(0.1119)	(0.1505)	(0.2185)
Net realized and unrealized gain (loss)	(1.3816)	(4.2132)	(5.9417)
Change in net asset value from operations	(1.4935)	(4.3637)	(6.1602)
Net asset value, ending balance	14.02	15.51	19.8744
Market value per share, beginning balance	15.51	19.80	25.98
Market value per share, ending balance	$ 14.09	$ 15.51	$ 19.80
Total Return, at net asset value	(9.60%)	(22.00%)	(23.70%)
Total Return, at market value	(9.20%)	(21.70%)	(23.80%)
Ratios to Average Net Assets
Expense ratio	0.95%	0.95%	0.95%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.71%)	(0.93%)	(0.91%)
ProShares Ultra Yen [Member]
Financial Highlights [Line Items]
Net asset value, beginning balance	$ 54.75	$ 56.4747	$ 74.5261
Net investment income (loss)	(0.4586)	(0.4787)	(0.6693)
Net realized and unrealized gain (loss)	1.1321	(1.2433)	(17.3821)
Change in net asset value from operations	0.6735	(1.7220)	(18.0514)
Net asset value, ending balance	55.43	54.75	56.4747
Market value per share, beginning balance	54.70	56.48	74.44
Market value per share, ending balance	$ 55.52	$ 54.70	$ 56.48
Total Return, at net asset value	1.20%	(3.00%)	(24.20%)
Total Return, at market value	1.50%	(3.20%)	(24.10%)
Ratios to Average Net Assets
Expense ratio	0.95%	0.95%	0.95%
Expense ratio, excluding brokerage commissions	0.95%	0.95%	0.95%
Net investment income (loss)	(0.69%)	(0.88%)	(0.90%)