Summary of Significant Accounting Policies - New Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2018	Sep. 30, 2019	Jan. 01, 2019
New Accounting Pronouncements
Operating lease liabilities				$ 518,612
Operating lease maturity payments
2019				3,706,042
2020				3,482,815
2021				3,104,755
2022				2,705,820
2023				2,238,693
Thereafter				6,157,395
Total				$ 21,395,520
Minimum
New Accounting Pronouncements
Discount rate				3.97%
Maximum
New Accounting Pronouncements
Discount rate				5.52%
Accounting Standards Update 2016-02 | Restatement Adjustment
New Accounting Pronouncements
Right-of use assets for operating leases					$ 524,000
Operating lease liabilities					$ 524,000
Accounting Standards Update 2016-02 | Proforma Adjustment
New Accounting Pronouncements
Lease expenses	$ 11,800	$ 34,100	$ 45,000