Goodwill and Other Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Unamortizable intangible assets:
Gross Carrying Amount	$ 124,222	$ 125,138
Amortizable intangible assets:
Gross Carrying Amount	2,800,228	2,612,936
Accumulated Amortization	(1,556,537)	(1,358,528)
Gross Carrying Amount, Total intangible assets	2,924,450	2,738,074
Management contracts
Unamortizable intangible assets:
Gross Carrying Amount	67,422	62,338
Trademark
Unamortizable intangible assets:
Gross Carrying Amount	56,800	56,800
Trade name
Unamortizable intangible assets:
Gross Carrying Amount	0	6,000
Customer relationships
Amortizable intangible assets:
Gross Carrying Amount	880,104	857,772
Accumulated Amortization	(603,866)	(519,162)
Mortgage servicing rights
Amortizable intangible assets:
Gross Carrying Amount	927,525	803,419
Accumulated Amortization	(370,634)	(319,927)
Trademarks/Trade names
Amortizable intangible assets:
Gross Carrying Amount	354,060	345,834
Accumulated Amortization	(111,595)	(92,730)
Management contracts
Amortizable intangible assets:
Gross Carrying Amount	152,312	142,767
Accumulated Amortization	(145,612)	(138,891)
Covenant not to compete
Amortizable intangible assets:
Gross Carrying Amount	73,750	73,750
Accumulated Amortization	(73,750)	(73,750)
Other
Amortizable intangible assets:
Gross Carrying Amount	412,477	389,394
Accumulated Amortization	$ (251,080)	$ (214,068)