Stock Incentive Compensation and Employee Benefit Plans (Equity Compensation Other than Options) (Details) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash Settled Restricted Stock Unit (CSRSUs)
Number of shares
Nonvested, beginning balance (in shares)	146,917	262,330	308,344
Awards granted (in shares)	0	0	98,067
Awards vested (in shares)	(80,012)	(108,344)	(122,088)
Awards forfeited (in shares)	(3,161)	(7,069)	(21,993)
Nonvested, ending balance (in shares)	63,744	146,917	262,330
Performance Shares
Number of shares
Nonvested, beginning balance (in shares)	152,451	167,673	211,381
Awards granted (in shares)	58,050	83,475	64,947
Awards vested (in shares)	(21,730)	(16,456)	(62,499)
Awards forfeited (in shares)	(43,924)	(82,241)	(46,156)
Nonvested, ending balance (in shares)	144,847	152,451	167,673
Weighted average grant-date fair value
Nonvested, beginning balance (in usd per share)	$ 57.21	$ 53.11	$ 44.63
Awards granted (in usd per share)	146.10	60.69	65.27
Awards vested (in usd per share)	49.90	53.79	43.51
Nonvested, ending balance (in usd per share)	$ 94.70	$ 57.21	$ 53.11
Employee restricted stock awards
Number of shares
Nonvested, beginning balance (in shares)	447,740	333,037	402,170
Awards granted (in shares)	242,832	255,799	116,345
Awards vested (in shares)	(165,245)	(139,454)	(185,478)
Awards forfeited (in shares)	(14,467)	(1,642)	0
Nonvested, ending balance (in shares)	510,860	447,740	333,037
Weighted average grant-date fair value
Nonvested, beginning balance (in usd per share)	$ 130.37	$ 120.93	$ 103.34
Awards granted (in usd per share)	146.92	132.70	148.66
Awards vested (in usd per share)	124.71	112.70	100.17
Awards forfeited (in usd per share)	136.16	134.38	0
Nonvested, ending balance (in usd per share)	$ 139.91	$ 130.37	$ 120.93
Non-employee director restricted stock awards
Number of shares
Nonvested, beginning balance (in shares)	22,534	20,126	25,545
Awards granted (in shares)	11,444	12,169	12,193
Awards vested (in shares)	(12,972)	(9,761)	(17,612)
Awards forfeited (in shares)	0	0	0
Nonvested, ending balance (in shares)	21,006	22,534	20,126
Weighted average grant-date fair value
Nonvested, beginning balance (in usd per share)	$ 132.29	$ 131.09	$ 107.95
Awards granted (in usd per share)	147.43	127.29	150.05
Awards vested (in usd per share)	131.88	123.59	110.66
Awards forfeited (in usd per share)	0	0	0
Nonvested, ending balance (in usd per share)	$ 140.79	$ 132.29	$ 131.09
Total restricted stock awards
Number of shares
Nonvested, beginning balance (in shares)	470,274	353,163	427,715
Awards granted (in shares)	254,276	267,968	128,538
Awards vested (in shares)	(178,217)	(149,215)	(203,090)
Awards forfeited (in shares)	(14,467)	(1,642)	0
Nonvested, ending balance (in shares)	531,866	470,274	353,163
Weighted average grant-date fair value
Nonvested, beginning balance (in usd per share)	$ 130.46	$ 121.51	$ 103.61
Awards granted (in usd per share)	146.94	132.79	148.79
Awards vested (in usd per share)	125.23	113.41	101.08
Awards forfeited (in usd per share)	136.16	134.38	0
Nonvested, ending balance (in usd per share)	$ 139.94	$ 130.46	$ 121.51

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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