Stockholders' Equity - Additional Information (Details) - USD ($)																																											12 Months Ended
	Dec. 27, 2021	Nov. 29, 2021	Nov. 12, 2021	Oct. 27, 2021	Sep. 27, 2021	Aug. 27, 2021	Jul. 27, 2021	Jun. 28, 2021	May 27, 2021	May 14, 2021	Apr. 27, 2021	Mar. 29, 2021	Feb. 26, 2021	Jan. 27, 2021	Dec. 28, 2020	Nov. 27, 2020	Oct. 27, 2020	Sep. 28, 2020	Aug. 27, 2020	Jul. 27, 2020	Jun. 29, 2020	May 27, 2020	Apr. 27, 2020	Mar. 27, 2020	Feb. 27, 2020	Jan. 29, 2020	Jan. 28, 2020	Jan. 27, 2020	Jan. 24, 2020	Jan. 23, 2020	Dec. 27, 2019	Nov. 27, 2019	Oct. 28, 2019	Sep. 27, 2019	Aug. 27, 2019	Jul. 29, 2019	Jun. 27, 2019	May 28, 2019	Apr. 29, 2019	Mar. 27, 2019	Feb. 27, 2019	Jan. 28, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Aug. 20, 2021	Aug. 19, 2021	Feb. 15, 2019
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																																											50,000,000	50,000,000
Preferred stock, par value (in dollars per share)																																											$ 0.001	$ 0.001
Preferred stock, undesignated shares authorized (in shares)																																											31,617,000
Proceeds from issuance of common stock																																											$ 328,780,000	$ 54,575,000	$ 321,860,000
Common stock, shares authorized (in shares)																																											200,000,000	125,000,000		200,000,000	125,000,000
Common stock, par value (in dollars per share)																																											$ 0.001	$ 0.001
Common stock, shares issued (in shares)																																											94,152,000	65,290,000
Common stock, shares outstanding (in shares)																																											94,152,000	65,290,000
Remaining shares authorized to be repurchased (in shares)																																											8,210,000	8,210,000
Common Stock
Class of Stock [Line Items]
Per Share price (in dollars per share)																																												$ 19.42	$ 17.77
Issuance of stock, net (in shares)																																											28,628,000	6,287,000	16,064,000
Proceeds from issuance of common stock																																											$ 29,000	$ 6,000	$ 16,000
At-The-Market Offering Program
Class of Stock [Line Items]
Preferred stock issued (in shares)										17,000
Common stock, shares authorized (in shares)																																																17,000
Common stock, par value (in dollars per share)										$ 0.001																																						$ 0.001
Sale of stock, commission rate										2.00%																																						2.00%
Common stock, additional shares authorized (in shares)			25,000,000
Common stock ATM Sales Agreement | Common Stock
Class of Stock [Line Items]
Per Share price (in dollars per share)																																											$ 12.07	$ 8.68	$ 20.98
Issuance of stock, net (in shares)																																											10,713,000		884,000
Proceeds from issuance of common stock																																											$ 129,336,000	$ 54,575,000	$ 18,540,000
Preferred stock issued (in shares)																																												6,287,000
2021 Common stock ATM Sales Agreement | Common Stock
Class of Stock [Line Items]
Per Share price (in dollars per share)																																											$ 11.13
Preferred stock issued (in shares)																																											17,915,000
Proceeds from issuance of preferred stock, net																																											$ 199,444,000
Series C Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																											10,000,000
Preferred stock, par value (in dollars per share)																											$ 0.001																$ 0.001
Preferred stock, dividend rate																											7.00%																7.00%	7.00%	7.00%
Preferred stock, liquidation preference per share (in dollars per share)																																											$ 25.00
Payments of dividends	$ 998,500	$ 998,500		$ 998,500	$ 998,500	$ 998,500	$ 998,500	$ 998,500	$ 998,500		$ 998,500	$ 869,600	$ 836,900	$ 779,700	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 773,400	$ 678,100																		$ 11,473,000	$ 8,412,000	$ 0
Preferred stock, shares issued (in shares)																																											6,847,000	5,347,000
Preferred stock, shares outstanding (in shares)																																											6,847,000	5,347,000
Preferred stock, aggregate liquidation preference																																											$ 171,175,000	$ 133,675,000
Unnissued preferred stock (in shares)																																											3,153,000
Accrued or unpaid dividends																																											$ 0
Proceeds from issuance of common stock																																											36,585,000	130,138,000
Proceeds from issuance of preferred stock, net																																											36,585,000	$ 130,138,000	$ 0
Series C Preferred Stock | January 23, 2020 Underwriting Agreement
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																														3,000,000
Preferred stock, par value (in dollars per share)																														$ 0.001
Preferred stock, dividend rate																														7.00%
Preferred stock, liquidation preference per share (in dollars per share)																														$ 25.00
Per Share price (in dollars per share)																														$ 25.00
Payments of stock issuance costs																											$ 2,968,000
Series C Preferred Stock | Preferred C Underwritten Offering
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																														450,000
Per Share price (in dollars per share)																																												$ 24.14
Over-allotment option term																														30 days
Issuance of stock, net (in shares)																											3,450,000
Proceeds from issuance of common stock																											$ 83,282,000																	$ 83,282,000
Preferred stock issued (in shares)																																												3,450,000
Series C Preferred Stock | January 29, 2020, Equity Sales Agreement
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)																										6,550,000
Proceeds from issuance of common stock																																											36,585,000	$ 46,856,000
Payments of stock issuance costs																																											445,000	$ 726,000
Preferred stock issued (in shares)																																												1,897,000
Series C Preferred Stock | At-The-Market Offering Program
Class of Stock [Line Items]
Payments of stock issuance costs																																											$ 1,682,000
Series B Preferred Stock
Class of Stock [Line Items]
Preferred stock, dividend rate																																											7.875%	7.875%	7.875%
Preferred stock, called for redemption (in shares)																													8,383,000
Preferred stock, liquidation preference per share (in dollars per share)																													$ 25.00
Payments of dividends																									$ 1,375,000			$ 1,375,000			$ 1,291,000	$ 1,210,000	$ 1,190,000	$ 1,168,000	$ 1,142,000	$ 1,100,000	$ 1,059,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 1,045,000	$ 0	$ 1,375,000	$ 13,385,000
Proceeds from issuance of common stock																																													49,795,000
Percent of outstanding shares intended to be redeemed																										2.00%
Proceeds from issuance of preferred stock, net																																											0	$ 0	$ 44,289,000
Series B Preferred Stock | 2021 Common stock ATM Sales Agreement
Class of Stock [Line Items]
Payments of stock issuance costs																																											$ 2,277,000
Series B Preferred Stock | Dividend Reinvestment Program
Class of Stock [Line Items]
Preferred stock issued (in shares)																																											1,500,000
Series A Preferred Stock
Class of Stock [Line Items]
Preferred stock, dividend rate																																											8.25%	8.25%	8.25%
Payments of dividends																																				$ 375,000	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 374,800	$ 0	$ 0	$ 2,249,000