5. Fair Value Measurements (Details)	Jun. 30, 2018 USD ($)
Total	$ 328,836
Level 1 [Member]
Total	0
Level 2 [Member]
Total	328,836
Level 3 [Member]
Total	0
Municipal obligations
Total	326,063
Municipal obligations | Level 1 [Member]
Total	0
Municipal obligations | Level 2 [Member]
Total	326,063
Municipal obligations | Level 3 [Member]
Total	0
Corporate obligations
Total	2,773
Corporate obligations | Level 1 [Member]
Total	0
Corporate obligations | Level 2 [Member]
Total	2,773
Corporate obligations | Level 3 [Member]
Total	$ 0