CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020 USD ($) Lease	Sep. 30, 2020 USD ($) Lease shares	Sep. 30, 2019 USD ($) shares	Jan. 01, 2019 USD ($)
Supplemental disclosures of non-cash investing and financing activities
Common stock issued through the dividend reinvestment plan (in shares) | shares		1,967	1,594
Common stock issued through the dividend reinvestment plan		$ 339	$ 314
Number of shares withheld to satisfy employees' tax withholding and other liabilities (in shares) | shares		73,103	83,602
Shares withheld to satisfy employees' tax withholding and other liabilities, value		$ 14,752	$ 15,961
Stock issued during period, shares, share-based compensation, forfeited (in shares) | shares		7,421
Stock issued during period, value, share-based compensation, forfeited		$ 1,187	305
Dividends declared but not paid	$ 225,025	225,025
Change in redemption value of redeemable noncontrolling interest	(62)
Cash flow hedge losses reclassified to earnings	2,367	6,617	4,825
Operating Lease, Right-of-Use Asset	135,885	135,885
Total lease liabilities	162,683	162,683
Increase (Decrease) in Derivative Liabilities			$ 17,824
Increase (Decrease) in Derivative Assets		$ 1,413
Restricted Stock and Restricted Stock Converted From Performance Shares
Supplemental disclosures of non-cash investing and financing activities
Equity instruments granted (in shares) | shares		165,426	150,359
Restricted Stock Converted From Performance Shares
Supplemental disclosures of non-cash investing and financing activities
Equity instruments granted (in shares) | shares		96,317	73,072
Restricted stock
Supplemental disclosures of non-cash investing and financing activities
Equity instruments granted (in shares) | shares		69,109	77,287
Fair value of shares issued		$ 15,285	$ 15,145
Stock issued during period, shares, share-based compensation, forfeited (in shares) | shares		7,421	1,730
Common stock
Supplemental disclosures of non-cash investing and financing activities
Dividends declared but not paid	223,391	$ 223,391	$ 213,070
Accumulated earnings less dividends
Supplemental disclosures of non-cash investing and financing activities
Change in redemption value of redeemable noncontrolling interest	(62)	(387)	$ 382
Accounting Standards Update 2016-02
Supplemental disclosures of non-cash investing and financing activities
Operating Lease, Right-of-Use Asset				$ 122,276
Total lease liabilities				$ 122,276
New Office Leases
Supplemental disclosures of non-cash investing and financing activities
Operating Lease, Right-of-Use Asset	$ 46,875	$ 46,875
Number of New Office Leases | Lease	2	2
Total lease liabilities	$ 46,875	$ 46,875