Partners' Capital, Equity and Incentive Compensation Plans - Schedule of Quarterly Cash Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands																		3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 15, 2020	Oct. 06, 2020	Jul. 15, 2020	Jul. 07, 2020	Apr. 15, 2020	Apr. 07, 2020	Jan. 15, 2020	Jan. 07, 2020	Jul. 15, 2019	Jul. 09, 2019	Apr. 15, 2019	Apr. 04, 2019	Jan. 15, 2019	Jan. 08, 2019	Jun. 25, 2018	Jun. 22, 2018	Mar. 15, 2018	Sep. 30, 2020	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Jun. 30, 2020
Dividend rate (as a percent)																	7.125%
Preferred stock, shares issued																	4,280,000
Preferred stock redemption price per share																		$ 25.00		$ 25.00
Threshold period of redemption of preferred stock																				120 days
Voting power threshold (as a percent)																		50.00%		50.00%
Convertible preferred stock par value																		$ 0.01		$ 0.01
Preferred stock, liquidation preference																	$ 25.00	25.00		25.00
Share cap price																		$ 1.46929		$ 1.46929
Net proceeds																				$ 285,480	$ 268,392
Preferred nits, issued (in shares)																	4,280,000
Series A Preferred Stock
Per Share and Per Unit Rate (in dollars per share)			$ 0.45		$ 0.45		$ 0.45		$ 0.45		$ 0.45		$ 0.45
Aggregate Dividend/Distribution Amount			$ 1,900		$ 1,900		$ 1,900		$ 1,900		$ 1,900		$ 1,900							$ 5,700	5,700
Series A Redeemable Perpetual Preferred Stock
Dividend rate (as a percent)																				7.125%		7.125%
Preferred stock, shares issued																		4,280,000		4,280,000		4,280,000
Preferred stock, liquidation preference																		$ 25.00		$ 25.00		$ 25.00
Series B Convertible Perpetual Preferred Stock
Dividend rate (as a percent)															6.50%	6.50%				6.50%		6.50%
Preferred stock, shares issued															3,162,500			3,162,500		3,162,500		3,162,500
Conversion rate																				2.1382
Minimum percentage of closing sale price of common stock under preferred stock conversion (as a percent)																				150.00%
Minimum trading days of closing sale price of common stock under preferred stock conversion (in days)																				20 days
Maximum trading days of closing sale price of common stock under preferred stock conversion including the last trading day (in days)																				30 days
Preferred stock, liquidation preference															$ 100.00			$ 100.00		$ 100.00		$ 100.00
Period of average daily volume weighted average price																10 days
Share cap price																		$ 5.1020		$ 5.1020
Series B Preferred Stock [Member]
Per Share and Per Unit Rate (in dollars per share)			$ 1.63		$ 1.63		$ 1.63		$ 1.63		$ 1.63		$ 1.63
Aggregate Dividend/Distribution Amount			$ 5,100		$ 5,100		$ 5,100		$ 5,100		$ 5,100		$ 5,100							$ 15,300	15,300
Subsequent Event | Series A Redeemable Perpetual Preferred Stock
Per Share and Per Unit Rate (in dollars per share)	$ 0.45
Subsequent Event | Series B Convertible Perpetual Preferred Stock
Per Share and Per Unit Rate (in dollars per share)	$ 1.63
Underwriter's Option
Preferred stock, shares issued																	280,000
Underwriter's Option | Series B Convertible Perpetual Preferred Stock
Preferred stock, shares issued															412,500
QualityTech, LP
Net proceeds																				$ 285,480	268,392
QualityTech, LP | Series A Redeemable Perpetual Preferred Units
Dividend rate (as a percent)																				7.125%		7.125%
Preferred stock, shares issued																		4,280,000		4,280,000		4,280,000
Preferred stock, liquidation preference																		$ 25.00		$ 25.00		$ 25.00
QualityTech, LP | Series B Redeemable Perpetual Preferred Units
Dividend rate (as a percent)																				6.50%		6.50%
Preferred stock, shares issued																		3,162,500		3,162,500		3,162,500
Preferred stock, liquidation preference																		$ 100.00		$ 100.00		$ 100.00
QualityTech, LP | Series B Convertible Perpetual Preferred Stock
Preferred stock, shares issued															3,162,500
Common stock
Per Share and Per Unit Rate (in dollars per share)				$ 0.47		$ 0.47		$ 0.44		$ 0.44		$ 0.44		$ 0.41
Aggregate Dividend/Distribution Amount				$ 31,500		$ 31,500		$ 28,600		$ 27,300		$ 27,300		$ 23,700						$ 91,600	$ 78,300
Shares issued																			4,000,000
Common stock | Subsequent Event
Per Share and Per Unit Rate (in dollars per share)		$ 0.47
Common stock | Underwritten Offering
Share price (in dollars per share)																							$ 64.90
Net proceeds																		$ 269,400