Acquisitions, Dispositions and Mortgage Repayments - Acquisitions (Details) $ in Thousands																																														12 Months Ended
	Dec. 30, 2021 USD ($) ft²	Dec. 29, 2021 USD ($) ft²	Dec. 28, 2021 USD ($) ft²	Dec. 20, 2021 USD ($) ft²	Dec. 02, 2021 USD ($) ft²	Dec. 01, 2021 USD ($) ft²	Nov. 18, 2021 USD ($) ft²	Nov. 15, 2021 USD ($) ft²	Sep. 30, 2021 USD ($) ft²	Sep. 22, 2021 USD ($) ft²	Sep. 20, 2021 USD ($) ft²	Aug. 19, 2021 USD ($) ft²	Jul. 27, 2021 USD ($) ft²	Jul. 19, 2021 USD ($) ft²	Jul. 16, 2021 USD ($) ft²	Jun. 29, 2021 USD ($) ft²	Jun. 28, 2021 USD ($) ft²	May 28, 2021 USD ($) ft²	May 14, 2021 USD ($) ft²	Mar. 03, 2021 USD ($) ft²	Feb. 17, 2021 USD ($) ft²	Feb. 01, 2021 USD ($) ft²	Jan. 07, 2021 USD ($) ft²	Dec. 30, 2020 USD ($) ft²	Dec. 29, 2020 USD ($) ft² property	Dec. 22, 2020 USD ($) ft²	Dec. 17, 2020 USD ($) ft²	Dec. 01, 2020 USD ($) ft²	Nov. 18, 2020 USD ($) ft²	Nov. 09, 2020 USD ($) ft² property	Oct. 22, 2020 USD ($) ft²	Oct. 07, 2020 USD ($) ft²	Sep. 28, 2020 USD ($) ft²	Sep. 24, 2020 USD ($) ft²	Sep. 04, 2020 USD ($) ft²	Jul. 31, 2020 USD ($) ft²	Jul. 23, 2020 USD ($) ft²	Jul. 17, 2020 USD ($) ft²	Jul. 01, 2020 USD ($) ft²	Mar. 13, 2020 USD ($) ft²	Mar. 09, 2020 USD ($) ft²	Feb. 25, 2020 USD ($) ft²	Feb. 13, 2020 USD ($) ft²	Jan. 14, 2020 USD ($) ft² property	Jan. 03, 2020 USD ($) ft²	Dec. 31, 2021 USD ($) ft² property	Dec. 31, 2020 USD ($) ft²	Oct. 21, 2021 USD ($)	May 10, 2021 USD ($)	Apr. 08, 2021 USD ($)	Apr. 01, 2021 USD ($)	Mar. 30, 2021 USD ($)	Dec. 08, 2020 USD ($)
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																																															$ 426,100
MORTGAGES ASSUMED																																															(35,800)
CASH CONSIDERATION																																															395,500
REAL ESTATE 2																																															432,300
OTHER																																															$ (1,000)
Purchase price allocation square footage | ft²																																															1,202,438
Operating lease right-of-use assets																																														$ 128,386	$ 125,198
Ground leases																													$ 400																	8,500	9,000
Below market lease																								$ 200					800
Operating lease liabilities																								600																						$ 96,138	92,273
Number of properties subject to ground leases | property																																														109
Financing lease liabilities																																														$ 22,551	18,837
Above-market lease intangibles																																														5,000	2,600
REAL ESTATE																																														179,862	121,600
Denver, CO
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
REAL ESTATE																																																$ 23,021				$ 14,550
Colorado Springs, CO
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
REAL ESTATE													$ 9,135																																						$ 7,347
Columbus, OH
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
Operating lease right-of-use assets																																														8,900
Los Angeles, CA
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
REAL ESTATE																																																	$ 24,147	$ 30,642
Medical Office Building
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																																														575,811	421,000
MORTGAGES ASSUMED																																														(11,000)	(35,800)
CASH CONSIDERATION																																														561,465	390,100
REAL ESTATE 2																																														562,824	426,900
OTHER																																														$ 9,641	$ (1,000)
Purchase price allocation square footage | ft²																																														1,540,141	1,202,438
Fair value adjustments included in Other																																														$ 800	$ 700
Number of properties acquired | property																														3
Medical Office Building | San Diego, CA
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																		$ 102,650					$ 17,150			$ 37,400													$ 16,700
MORTGAGES ASSUMED																		0					0			(16,500)													0
CASH CONSIDERATION																		103,984					17,182			21,400													16,700
REAL ESTATE 2																		104,629					17,182			38,500													16,900
OTHER																		$ (645)					$ 0			$ (600)													$ (200)
Purchase price allocation square footage | ft²																		160,394					22,461			45,157													46,083
Medical Office Building | Dallas, TX
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																						$ 22,515
MORTGAGES ASSUMED																						0
CASH CONSIDERATION																						22,299
REAL ESTATE 2																						22,641
OTHER																						$ (342)
Purchase price allocation square footage | ft²																						121,709
Medical Office Building | Atlanta, GA
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2	$ 4,900																				$ 9,800				$ 50,000											$ 20,500							$ 12,000
MORTGAGES ASSUMED	0																				0				0											0							0
CASH CONSIDERATION	4,772																				10,027				50,400											21,600							11,800
REAL ESTATE 2	4,419																				10,073				50,600											21,300							12,100
OTHER	$ 353																				$ (46)				$ (200)											$ 300							$ (300)
Purchase price allocation square footage | ft²	11,840																				44,567				125,404											48,145							64,624
Number of properties acquired | property																									2
Medical Office Building | Washington, DC
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																				$ 12,750
MORTGAGES ASSUMED																				0
CASH CONSIDERATION																				12,709
REAL ESTATE 2																				12,658
OTHER																				$ 51
Purchase price allocation square footage | ft²																				26,496
Medical Office Building | Houston, TX
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																			$ 13,500															$ 11,000
MORTGAGES ASSUMED																			0															0
CASH CONSIDERATION																			12,986															10,900
REAL ESTATE 2																			13,379															11,000
OTHER																			$ (393)															$ (100)
Purchase price allocation square footage | ft²																			45,393															40,235
Medical Office Building | Greensboro, NC
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2														$ 6,400			$ 9,390							11,600			$ 10,500			$ 45,100
MORTGAGES ASSUMED														0			0							0			0			0
CASH CONSIDERATION														6,374			9,475							11,300			10,800			45,400
REAL ESTATE 2														6,514			10,047							11,300			10,700			44,900
OTHER														$ (140)			$ (572)							$ 0			$ 100			$ 500
Purchase price allocation square footage | ft²														18,119			25,168							35,373			27,599			149,400
Medical Office Building | Baltimore, MD
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																$ 14,600
MORTGAGES ASSUMED																0
CASH CONSIDERATION																14,357
REAL ESTATE 2																14,437
OTHER																$ (80)
Purchase price allocation square footage | ft²																33,316
Medical Office Building | Denver, CO
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2							$ 22,400	$ 7,700		$ 20,250					$ 70,426																									$ 33,500
MORTGAGES ASSUMED							0	0		0					0																									0
CASH CONSIDERATION							22,343	7,383		19,630					69,151																									33,200
REAL ESTATE 2							22,422	7,431		19,405					65,100																									34,000
OTHER							$ (79)	$ (48)		$ 225					$ 4,051																									$ (800)
Purchase price allocation square footage | ft²							30,185	18,599		83,604					259,555																									136,994
Number of properties acquired | property																																														3
Medical Office Building | Colorado Springs, CO
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2				$ 10,575									33,400																			$ 8,900									$ 8,200
MORTGAGES ASSUMED				0									0																			0									0
CASH CONSIDERATION				10,541									32,738																			8,900									8,300
REAL ESTATE 2				11,009									33,241																			9,000									8,600
OTHER				$ (468)									$ (503)																			$ (100)									$ (300)
Purchase price allocation square footage | ft²				44,166									69,526																			36,720									34,210
Medical Office Building | Birmingham, AL
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2												$ 9,250
MORTGAGES ASSUMED												0
CASH CONSIDERATION												9,355
REAL ESTATE 2												9,388
OTHER												$ (33)
Purchase price allocation square footage | ft²												29,942
Medical Office Building | Raleigh, NC
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2									$ 10,000		$ 5,780																															$ 6,300
MORTGAGES ASSUMED									0		0																															0
CASH CONSIDERATION									9,921		5,821																															6,500
REAL ESTATE 2									9,874		5,810																															6,500
OTHER									$ 47		$ 11																															$ 0
Purchase price allocation square footage | ft²									29,178		18,280																															15,964
Medical Office Building | Columbus, OH
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2			$ 9,525			$ 16,275
MORTGAGES ASSUMED			0			0
CASH CONSIDERATION			9,521			15,970
REAL ESTATE 2			9,601			7,365
OTHER			$ (80)			$ 8,605
Purchase price allocation square footage | ft²			28,962			71,930
Number of properties acquired | property																																														2
Financing lease receivable						$ 7,400																																								$ 7,400
Imputed lease arrangement						$ 8,900																																								$ 8,900
Medical Office Building | Los Angeles, CA
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2			$ 20,500																														$ 14,000					$ 35,000							$ 42,000
MORTGAGES ASSUMED			(11,000)																														0					0							(19,300)
CASH CONSIDERATION			9,396																														14,000					37,700							22,800
REAL ESTATE 2			20,316																														13,900					37,700							42,400
OTHER			$ 80																														$ 100					$ 0							$ (300)
Purchase price allocation square footage | ft²			56,762																														24,252					49,785							86,986
REAL ESTATE																									$ 13,100																												$ 79,200
Medical Office Building | Austin,TX
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2		$ 20,500
MORTGAGES ASSUMED		0
CASH CONSIDERATION		20,696
REAL ESTATE 2		20,741
OTHER		$ (45)
Purchase price allocation square footage | ft²		62,548
Medical Office Building | Nashville, TN
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2	$ 54,000	$ 19,775			$ 11,300																							$ 14,000
MORTGAGES ASSUMED	0	0			0																							0
CASH CONSIDERATION	53,923	19,833			11,245																							13,900
REAL ESTATE 2	54,072	19,982			11,263																							13,900
OTHER	$ (149)	$ (149)			$ (18)																							$ 0
Purchase price allocation square footage | ft²	74,489	85,590			34,908																							38,736
Medical Office Building | Seattle, WA
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																																					$ 11,000
MORTGAGES ASSUMED																																					0
CASH CONSIDERATION																																					10,900
REAL ESTATE 2																																					11,300
OTHER																																					$ (400)
Purchase price allocation square footage | ft²																																					21,309
Medical Office Building | Memphis, TN
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																													7,000	$ 26,300
MORTGAGES ASSUMED																													0	0
CASH CONSIDERATION																													7,100	26,500
REAL ESTATE 2																													6,100	26,200
OTHER																													$ 1,000	$ 300
Purchase price allocation square footage | ft²																													40,192	135,270
Medical Office Building 2 | Nashville, TN
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2	$ 20,500
MORTGAGES ASSUMED	0
CASH CONSIDERATION	19,833
REAL ESTATE 2	19,825
OTHER	$ 8
Purchase price allocation square footage | ft²	32,454
Land
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
PURCHASE PRICE 2																															$ 2,500				$ 1,000									$ 1,600
MORTGAGES ASSUMED																															0				0									0
CASH CONSIDERATION																															2,600				1,100									1,700
REAL ESTATE 2																															2,600				1,100									1,700
OTHER																															$ 0				$ 0									$ 0
Purchase price allocation square footage | ft²																															0				0									0
Number of properties subject to ground leases | property																																												4
Land | Nashville, TN
Real Estate Acquisitions and Mortgage Note Financing [Line Items]
Adjacent land parcel | ft²																																														2.7