Property and Equipment (Property and Equipment, Including Original Useful Lives) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Property and Equipment
Property and equipment	$ 5,191,135	$ 4,832,342
Less: accumulated depreciation and amortization	1,847,329	1,708,911
Net property and equipment	3,343,806	3,123,431
Land [Member]
Property and Equipment
Property and equipment	695,669	648,689
Buildings and building improvements [Member]
Property and Equipment
Property and equipment	$ 1,968,079	1,805,347
Buildings and building improvements [Member] \| Minimum [Member]
Property and Equipment
Property and equipment, useful lives	15 years
Buildings and building improvements [Member] \| Maximum [Member]
Property and Equipment
Property and equipment, useful lives	39 years
Leasehold improvements [Member]
Property and Equipment
Property and equipment	$ 626,714	593,785
Leasehold improvements [Member] \| Minimum [Member]
Property and Equipment
Property and equipment, useful lives	3 years
Leasehold improvements [Member] \| Maximum [Member]
Property and Equipment
Property and equipment, useful lives	25 years
Furniture, fixtures and equipment [Member]
Property and Equipment
Property and equipment	$ 1,250,690	1,215,929
Furniture, fixtures and equipment [Member] \| Minimum [Member]
Property and Equipment
Property and equipment, useful lives	3 years
Furniture, fixtures and equipment [Member] \| Maximum [Member]
Property and Equipment
Property and equipment, useful lives	20 years
Vehicles [Member]
Property and Equipment
Property and equipment	$ 392,130	359,362
Vehicles [Member] \| Minimum [Member]
Property and Equipment
Property and equipment, useful lives	5 years
Vehicles [Member] \| Maximum [Member]
Property and Equipment
Property and equipment, useful lives	10 years
Construction in Progress [Member]
Property and Equipment
Property and equipment	$ 257,853	$ 209,230

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(14))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(8))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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