Debt (Schedule of Cash and Non-Cash Interest Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Debt Instrument [Line Items]
Cash Interest	$ 90,544	$ 95,687	$ 180,639	$ 191,538
Non-cash Interest	$ 11,812	2,337	$ 23,615	4,743
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	1.60%		1.60%
Cash Interest	$ 1,573	1,661	$ 3,721	4,375
2018 Term Loan [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	1.872%		1.872%
Cash Interest	$ 11,067	20,950	$ 22,064	43,152
Non-cash Interest	$ 11,438	2,030	$ 22,872	4,052
Blended rate			1.872%
Accruing interest rate	1.86%		1.86%
2013 Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	3.722%		3.722%
Cash Interest	$ 5,396	5,396	$ 10,792	10,792
2014 Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	3.869%		3.869%
Cash Interest	$ 6,046	6,046	$ 12,092	12,092
2015-1C Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	3.156%		3.156%
Cash Interest		3,985		7,969
2016-1C Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	2.877%		2.877%
Cash Interest		5,090		10,181
2017-1C Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	3.168%		3.168%
Cash Interest	$ 3,115	6,088	$ 9,201	12,173
2018-1C Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	3.448%		3.448%
Cash Interest	$ 5,570	5,570	$ 11,141	11,141
2019-1C Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	2.836%		2.836%
Cash Interest	$ 8,357	8,357	$ 16,714	16,714
2020-1C Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	1.884%		1.884%
Cash Interest	$ 3,598		$ 7,195
2020-2C Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	2.328%		2.328%
Cash Interest	$ 3,540		$ 7,079
2021-1C Tower Securities [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	1.631%		1.631%
Cash Interest	$ 2,550		$ 2,550
2014 Senior Notes [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	4.875%		4.875%
Cash Interest				3,352
Non-cash Interest		275		112
2016 Senior Notes [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	4.875%		4.875%
Cash Interest	$ 13,406	13,406	$ 26,813	26,813
Non-cash Interest	$ 289	32	$ 575	547
2017 Senior Notes [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	4.00%		4.00%
Cash Interest		7,500	$ 2,333	15,000
2020 Senior Notes [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	3.875%		3.875%
Cash Interest	$ 14,531	11,571	$ 29,063	17,707
Non-cash Interest	$ 85		$ 168	32
2021 Senior Notes [Member]
Debt Instrument [Line Items]
Interest Rates as of March 31, 2021	3.125%		3.125%
Cash Interest	$ 11,719		$ 19,792
Other [Member]
Debt Instrument [Line Items]
Cash Interest	76	$ 67	89	$ 77
Interest Rate Swap [Member] | 2018 Term Loan [Member]
Debt Instrument [Line Items]
Notional amount	$ 1,950,000		$ 1,950,000
Derivative fixed interest rate	1.874%		1.874%
Interest Rate Swap [Member] | London Interbank Offered Rate (LIBOR) [Member] | 2018 Term Loan [Member]
Debt Instrument [Line Items]
Derivative basis spread on variable interest rate	1.75%		1.75%