Balance Sheet Components - Leases (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019	Jan. 01, 2019
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets	$ 1,031,000	$ 1,031,000
Non-current operating lease liabilities	952,678	952,678
Total lease liabilities	1,113,619	1,113,619
Lease Cost:
Lease costs	105,000	307,000
Operating lease cost	57,000	148,000
Short-term lease cost	48,000	159,000
Cash paid for operating lease liabilities	51,767	130,740
Right-of-use assets obtained in exchange for new operating lease obligations	$ 77,549	$ 1,150,443
Weighted-average remaining lease term	8 years 2 months 12 days	8 years 2 months 12 days
Weighted-average discount rate	5.30%	5.30%
Operating lease, liability, leases not commenced	$ 1,146,000	$ 1,146,000
ASU 2016-02
Lessee, Lease, Description [Line Items]
Operating lease right-of-use assets			$ 743,000
Non-current operating lease liabilities			$ 813,000
Minimum
Lessee, Lease, Description [Line Items]
Lease term of contract	1 year	1 year
Lease renewal term	1 year	1 year
Lease Cost:
Lease not yet commenced, term of contract	1 year	1 year
Maximum
Lessee, Lease, Description [Line Items]
Lease term of contract	15 years	15 years
Lease renewal term	15 years	15 years
Lease Cost:
Lease not yet commenced, term of contract	15 years	15 years